AI content, AI bots in the forums, AI telemarketing, AI answering machines, AI everything. AI will make IRL and stuff like audited national encyclopedias important again. Gone is the promise of the internet. And this is the real reason why anonymity will not be possible online. If we can't identify the poster as a human, it will mean nothing...
And since we don't have any of our constitutional rights to privacy online, an internet without anonymity isn't an acceptable solution either. What a waste. The most exciting and promising creation of the last hundred years, squandered for advertising and selfish means.
I honestly think anonymity is even better now, given the fact that you can self-host LLMs that can change the linguistic style of your writing into something entirely different.