Instances in the fediverse come and go for their own reasons or no reasons, for reasons I'd like and reasons I'd not like and mostly for reasons I'll never know and it's not my business.
It seems like there would be a way to see instances come into and go out of existence on a timeline by looking at the existing public data. Maybe that tool already exists.
I am curious which instances are longer-lasting, and if there's a relation between members and duration.