They come and go. They're random clutter. We only need a few big instances that hosts a majority of the communities and that's it. Why do we need so many smaller ones?
Lemm.ee that you're on has 25,718 users but only 2232 are active, that's a really small number. Lemmy.world that you're posting into is number 9 with 11,500 active users, that's still super small tbf.