Many ActivityPub services allow you to seamlessly transfer your profile from one instance to another. It even sends messages that let your followers update so they follow you at your new address. Moving profiles isn’t a big deal. It’s Ok if they join a big instance at first, and move later.
But do people know that? Not a rhetorical question, I only have direct experience with kbin and only a week's worth at that. I had only the very foggiest idea what all of this was when I came to kbin and signed up. I've learned a lot more since then, but I'm still brand new to this.
If I have no complaints with kbin, why would I be motivated to look for a new instance? Should I be looking anyway? What compelling reasons exist to shop around, as it were?
There are compelling reasons why new folks join big instances and it’s not definitely a bad thing
Seems like the natural progression of this sort of thing, no? Has enough time even passed to tell if this is a problem or not? This is a bit of an aside, but I feel like there's been a lot of doomposting the last few days about imagined future problems. Have we really had enough time to make any actionable observations?
Multiple accounts is not the same thing as abandoning your profile and instance to start over somewhere else. I have more than one profile right here on kbin, for example.
Regardless, you’ve ignored the entire rest of my comment, and kinda the whole point; people don’t know. How could they know? Where are they going to learn if not here, and once they are here, why leave?