Is it true that 5G will accelerate your site, or is it just a mirage?

Why doesn't 5G solve the web performance problem?

Martin Splitt points out an unyielding historical fact: every technological leap in bandwidth (from 2G to 3G, and 3G to 4G) has been accompanied by an equivalent inflation in page weight. Developers have systematically used the leeway provided by new infrastructures to enrich their sites — high-definition videos, interactive content, additional third-party scripts.

The result? Average load times have not structurally decreased. 5G promises theoretical speeds up to 10 times higher than 4G, yet Google anticipates the same pattern: this capacity will be used for new use cases (virtual reality, 8K streaming, real-time applications) rather than to speed up existing pages.

For an SEO practitioner, this analysis shifts the perspective: you cannot rely on network infrastructure to fix the performance shortcomings of your pages. Core Web Vitals will remain demanding, regardless of the dominant mobile network generation.

What is the economic logic behind this ongoing inflation?

Product and marketing teams naturally push for more visual richness, more interactivity, more tracking. Each department adds its tools: advanced analytics, A/B testing, chatbots, personalized recommendations. The available bandwidth becomes a resource to exploit, not a safety margin to maintain.

This mechanism resembles Parkinson's law applied to web performance: the weight of a page expands to saturate the available bandwidth. Modern JavaScript frameworks, third-party libraries, and media resources consume the surplus before the end user can benefit.

For SEO, this means a defensive approach — actively monitoring performance debt — is more relevant than a passive approach that relies on network improvements.

How does this dynamic concretely impact SEO?

Google has integrated speed as an explicit ranking factor with Core Web Vitals. However, these metrics measure actual user experience, not the theoretical capability of the network. A site loading 5 MB of JavaScript will remain slow in 5G if parsing and execution block rendering.

The real SEO battle thus lies in optimizing code, prioritizing critical resources, and reducing unnecessary weight. Sites that maintain strict discipline (rigorous lazy loading, aggressive compression, well-configured CDN) will retain a competitive advantage.

5G could even create a perverse effect: if your competitors bloat their pages assuming new networks' tolerance, they risk penalizing users still on 4G or with degraded connections — and Google measures performance across all audience segments.

• Bandwidth increases, but page weight does too — it's a constant balance, not a net improvement
• Core Web Vitals measure actual experience, regardless of theoretical network technology
• Relying on 5G to compensate for technical debt is a doomed strategy
• Disciplined sites maintain an advantage because they do not saturate available bandwidth
• Google evaluates cross-network performance — neglecting 4G or 3G remains risky for SEO

Does this statement align with real-world observations?

Absolutely. Data from HTTP Archive confirms that the median weight of a web page has skyrocketed: from ~500 KB in 2010 to over 2 MB today, with peaks between 3-4 MB for e-commerce or media sites. This inflation has occurred precisely during the rollout of 4G.

The SEO audits I conduct consistently reveal the same pattern: sites accumulate legacy code, unreviewed third-party scripts, and unoptimized assets. Bandwidth serves as a temporary fix rather than a leverage for improvement. Martin Splitt identifies a genuine structural issue, not a theory.

What is lacking in his statement? Concrete data on the correlation between 4G rollout and page weight inflation. The assertion is solid, but it would benefit from internal Google data — particularly geographically, to see if markets with early 4G adoption experienced faster inflation. [To be verified]

What biases should be anticipated in interpreting this position?

Google has a clear interest in keeping sites performing well: fast pages reduce bounce rates, increase engagement, and ultimately generate more advertising revenue. Martin's position can therefore be interpreted as a disguised incentive to maintain technical discipline.

But this bias does not disqualify the argument. The alignment of interests between Google and users is real: no one benefits from websites becoming 10 MB behemoths. The nuance is that Google could also improve its own tools (AMP, Cache, native Brotli in Chrome) to limit damage — and it is, partially.

A potential blind spot: Google may underestimate the positive impact of reduced latency in 5G. If page weight stagnates (optimistic assumption), the reduction in round-trip time could still improve TTFB and LCP. But betting on that without optimizing the rest would be naive.

In what cases does this rule not completely apply?

Sites with strict technical governance — often tech pure players or platforms with strong business constraints (finance, health) — do not necessarily follow this trend. They maintain fixed performance budgets, automate audits, and refuse unjustified additions.

Similarly, well-designed Progressive Web Apps (PWAs) leverage 5G differently: they aggressively cache locally and use bandwidth for background updates, not to inflate the initial payload. These architectures can genuinely benefit from 5G without degrading the experience.

Finally, in certain verticals (news, social media), media content is inherently heavy and balancing performance/richness is complex. For these players, 5G may offer some leeway — but it will likely be consumed by even richer formats (interactive 4K video, lightweight AR), confirming Martin's thesis.

What specific actions should you take to avoid experiencing this inflation?

The first action: set a performance budget and monitor it continuously. Establish a strict limit (for example, 1.5 MB for total initial weight, 300 KB of JavaScript) and refuse any addition that exceeds this threshold without an equivalent removal elsewhere. This requires strong political compromise, but it's the only way to avoid slippage.

The second lever: audit and clean existing code. Many websites contain outdated third-party scripts, unnecessary polyfills, or redundant libraries. A quarterly audit with tools like Lighthouse, WebPageTest, or SpeedCurve can identify quick wins. Automate regression detection through CI/CD.

The third focus: prioritize critical resources. Use preloading (preload), deferred loading (defer, async), and lazy loading for images and iframes. 5G will never absolve you from optimizing render order — it’s even more crucial if your competitors are inflating their pages.

What mistakes should you absolutely avoid?

Don't fall into the trap of “We’ll optimize later, 5G is coming”. This mindset leads to accumulating technical debt that becomes exponentially more expensive to fix. Every added script, every additional dependency creates interdependencies that rigidify the code.

Avoid also over-optimizing for one user segment at the expense of others. If you design solely for 5G, you penalize users in rural areas, roaming, or with limited plans. Google measures Core Web Vitals on the 75th percentile — thus across varied connections.

Finally, do not underestimate the SEO impact of third-party resources. Ad tags, social widgets, and tracking tools are often the main culprits behind slowness. If you cannot remove them, isolate them (sandbox, strict defer) and measure their real ROI.

How can you check if your strategy remains relevant with 5G?

Use Chrome DevTools in 5G throttling to simulate the future experience — but also test in 4G and 3G to not lose sight of the current landscape. Tools like PageSpeed Insights or CrUX provide real-world data on performance by connection type.

Set up automatic alerts on your Core Web Vitals metrics (LCP, INP, CLS). If a deployment degrades these indicators, immediate rollback. Technical discipline relies on visibility and responsiveness, not good intentions.

Finally, monitor the weight of your direct competitors using tools like SimilarWeb or regular audits. If you notice they are inflating their pages without losing ranking, it’s either they’re compensating through other levers (authority, content), or they’re taking a risk — and Google will eventually correct that. Stay the course.

• Define a strict performance budget (max weight, max JS) and monitor it automatically
• Audit quarterly to remove outdated or redundant resources
• Prioritize loading of critical resources (preload, defer, lazy loading)
• Test performance across multiple connection types (5G, 4G, 3G) via DevTools
• Automate alerts on Core Web Vitals to detect regressions
• Isolate and measure the ROI impact of third-party scripts before maintaining them