I think the invites feature is the only things bluesky really has. At this point, I don't mind as much as the feature allowed me to control who is in my feed and made my feed more intimate like the early days of Facebook. For me, it was a way to weirdly combat parasocial relationships by inviting people I know and talk to.
Theoretically. I can do the same for mastodon. But once I start trying to explain fediverse, they didn't care for it. Fediverse idea is interesting, but loses most people I want to keep in touch with.
Because it is harder to get people I know on board to mastodon than to bluesky. I don't want too many random people on my feed. Most of my feed consists of people I do know and actually interact with. Mastodon doesn't have as much shitposting as I would like and takes awhile for it to get situated to the point I ended not using it. Why bother going to mastodon when I have my friends on bluesky.