I don't think it's coordinated, I think it all starts from the same root cause: Silicon Valley Bank failed. These companies all need to do something they've really not done much of in the past: turn a profit. But these companies are not run by the business geniuses we were once convinced were running the show. Most of them live so far removed from a normal persons life that they don't understand what motivates us, what we want in a platform, and as soon as we provide feedback after they've already made a decision, they decide it's because we don't understand the squeeze they're under to make money.
Twitter: Elon Musk thinks he could make more money from subscriptions than advertisements. The whole thing's a disaster because that's really dumb. This case may be a little different though because there's some evidence Musk just wanted more people to see his tweets and to pay people to be his friend
Reddit: Spez fails to see that he has multiple revenue sources available to him so long as he keeps his users around. Somewhere, there was the right balance of charging for the API at a reasonable price, performing better market research on his user base to provide a better ad platform, and keeping the Reddit coin system in place as the base liked it because the user base paid more for that than most similar online payment schemes.
Google: this is the scary one. This is the one that seems like they know exactly what they're doing. They're ramping up their enshittification following the fall of SVB, but the way they're doing it is both malicious and a minor enough inconvenience that the majority of their users will stay. And they're doing it in small quiet ways. A little bit of tweaking how YouTube bans users here. A little bit of RFCs about DRM on the web there. Some PRs to chromium and android no one will notice. All to squeeze more ads into peoples online experiences. Their search product has been utter shit for about 6 years now, but people still prefer it over Bing or DuckDuckGo (which is a wrapper for Bing). They've learned the following lesson: if you're big enough, the citizens of the web will let you do it