Sure, but why Instagram specifically? Is this just first-mover/early-mover advantage or is IG better at something?

> Sure, but why Instagram specifically?

Because Instagram is specifically the place that those people already are. It really isn't hard to understand why others join it. They weren't even first, just the place where people ended up being, until they won't be there anymore and instead it'll be another place.

Also matters what niche/community you're a part of, some of them already left Instagram for other places (like furries seems to have gone to Mastodon/Bluesky as far as I can tell [but not a furry, so please don't sue me if I'm wrong]) while others are still there, like most musicians/artists still seem to prefer Instagram, even non-mainstream ones.

I think that's because that for me personally, I am genz and my generation / my school friends are just hooked up onto it. Literally 99% of my schoolmates were there.

It was the only way that I can keep in touch with my schoolmates / friends for years and though I have their number, we don't have any group chat aside from instagram and I use beeper to actually make it sane to use

Some of the reason might be that you don't need to share your phone number for it.