It is similar to Bluesky, yes. They both got a lot of inspiration from Twitter (before Musk turned it to shit/X).

And I would say that the discussions are more shallow than on Lemmy. Even though Mastodon has a higher character limit than Twitter and many Mastodon instances effectively remove the character limit, it’s still fundamentally a platform for shortform interactions. Infodumping is rarely seen, because you need to create a silly number of chained messages.

On the flipside, though, you get to know people. I do appreciate the time I spent on Mastodon, because of that. It’s a very different perspective as not everything is about discussing cold hard facts, but rather also people’s hobbies and struggles and whatnot.