It’s mostly just media first but there are a few features that don’t federate. Portfolios and stories are exclusive to pixelfed. And even if you just want to scroll a bunch of photos there just isn’t a better way. They have the best Fediverse app I’ve ever used and the experience is great because it was designed specifically for that purpose.
Not that there’s anything wrong with not seeing the appeal. The best thing about the Fediverse is that you can just be wherever you want. So you can post on Mastodon and follow whoever you want on Pixelfed too without having to make another account.