Cory Doctorow termed it “Enshittification”, and wrote about the process here: https://pluralistic.net/2023/01/21/potemkin-ai/#hey-guys

Ultimately a for-profit social platform can only make money via advertising. If you are depending on advertisers to be profitable you become beholden to those advertisers. Advertisers do not care about “community,” “sustainability,” or what made the platform attractive to users in the first place. But they do care about “public perception,” and “number of users,” and most importantly number of impressions per user, per hour. The advertisers customers care about things that hurt their branch, so they dont’ want NSFW content, they don’t want violent content, they don’t want controversial content, they don’t want anti-capitalist content, they want “quality” impressions.

So if you are twitter or reddit, or facebook, or whatever, if your advertisers make a demand that will piss off your users and make it worse for them you will always do it and you will continue to do it until the platform dies.