Advertising doesn't seem like a large enough lever to drive something this globally coordinated.
My read is that governments and large institutions are preparing for the kind of systemic instability climate change is going to produce.
Across the world we're already seeing laws and policies that quietly restrict the ability to organise, protest, or remain anonymous online, while surveillance capabilities expand at the same time. None of this is particularly popular, yet it keeps happening.
Why?
Because the next few decades are likely to involve continuous pressure from climate-driven problems: migration, water shortages, falling crop yields, energy instability, and the political conflict that follows when resources get tighter.
From that perspective, universal ID verification online isn't mainly about ads or "protecting the kids". It's about mapping who is who, who talks to who, and how information spreads.
If you expect future mass unrest, protest movements, or large-scale political instability, that kind of data becomes extremely valuable.
And historically, elites often choose to invest more effort in managing the consequences of systemic problems than in solving the underlying causes.
So instead of "AI spam broke advertising", the bigger story might be that institutions are building the infrastructure to monitor and manage populations during a much messier future.

