What? Ever heard anybody say "follow me on Twitter, Instagram and Youtube"? There are plenty more, all have a niche. Snapchat, Twitch, Tiktok, you name it. It's already a pluralistic world, and one more participant in the "open and free" niche is likely to have its place and fans.
I have around 80 followers in the Fediverse. (I have a “locked” profile which means I manually approve follow requests, mostly to keep trolls and bots away.) That’s not a very impressive number. It still is quite enough though‚ I don’t complain about the current level of interaction. Quality beats quantity.
Unlike Facebook, none of my relatives or middle school buddies are there – and to me that’s a good thing. To me, Facebook is way too large-scale for posting casual status updates.