Steemit is definitely the most popular in the crypto space and till date no other has succeeded in beating it. However, talking about trends in the crypto space, it is something that happens often and most times the projects that starts the trend are the legit ones because the idea in the onset is unique but then, others that comes after, a good number of them are just there to follow the hype and scam; this case scenario can be likened to that of social network trends. Now currently, it is Defi projects although the hype is diminishing some are still coming up, out of which few are genuine as well.
Furthermore, I think it will be difficult for people to stop using Facebook, Twitter etc for a crypto based social network, this is because those platforms has stood the test of time and hence having massive users, not only that, they keep improving to sustain their growth. However, it can still be possible if the crypto based social network will offer exceptional services.
I agree that successful social media in the cryptocurrency space is steemit. Even though there are many projects working on social media projects, I think people will still use Facebook or existing social media platforms because not everyone knows about cryptocurrency projects.