The real risk isn’t really Meta, or Reddit, or whatever coming in and shitting on everything, but rather the same thing that happened on Reddit: upvote bots, bought and paid for mods, communities that get astroturfed by corporations with fake reviews/“questions” about if a cool new product is, in fact, cool/“hey i just found this thing!” posts and so on.
Those aren’t as immediately obviously toxic as lemmy.facebook.com would be, but they’re still a corrupting influence that degrades the experience for everyone, and they do it in a way that’s less obvious to a lot of people because I mean, is it just a random person, or is it a paid-for shillbot?
Still, have to be careful of Meta federating their piles of users, but it’s not really the risk that’s likely to happen in the short term as much as “social media marketers” shitting things up the way they shit up everything they get anywhere near.