It seems unlikely to me. I especially don't see how social media are supposed to be speeding up dialectal diversification. If anything, I'd expect a leveling effect as speakers from all over are exposed to the same content.

Yes, the geographical nature of SM means they must level *geographical* differences a bit. But the SM environment is generally youthful & fashion-conscious, so the incidence of neologisms and buzzwords on SM is high, & can seem aggressive.

Think it's like this: A huge amount of TikTok/YouTube stuff is produced by non-native speakers and the most popular stuff usually uses very simple lexis and syntax to appeal to the widest audience. Young people are being exposed to that & older people aren't at all, so there's a generational divide.