Twitter pissed off their advertisers by pulling back content moderation. That is their biggest problem in terms of cash flow.

They're currently forcing logged-in users to share screenshots if they want to share something with non-logged-in friends and preserve any context whatsoever (you can no longer see replies, or what a xit was in response to, if you're not logged in—all you can see is a single xit). Search also doesn't work anymore if you're not logged in, and if you visit a user's page, their xits are ordered by some even-more-nonsensical-than-usual algo that puts years-old xits near the top. The site's basically totally unusable if you don't have an account.

This may be making some metric (account signups, presumably?) go up, but sure seems risky to me.

On Twitter and Reddit, the users most affected were also the people providing most value to the platform (tweets, reddit submissions, discussion, moderation). They're fairly symmetric platforms.

On YT, the people providing the value are the content creators. That is the same content creators who get a revenue share from ads and premium. They're the ones who benefit the most from blocking ad blockers. The people watching videos with ad blockers (and sponsor block)? They're not providing anything in exchange, to the platform or the creators.