I think it's useful when someone starts their account and isn't sure who to follow, or if I were to unexpectedly lose my contact list then I may do that as well. But I agree from there it's good to be a bit choosier. It makes your feed what you want it to be. I just laugh a little when I see people complain that nostr is slow or boring, and then I check and they only follow a few people. They are used to algorithms and suggested content on other platforms. On nostr you mostly just see who you follow, and people aren't used to that.