Well most of the complexity would be hidden. For example the Mastodon mobile client hides much of it. You can even sign up for a server there.
My main concern is the overlap between lemmy instances, meaning me and my mate can be looking at for example a channel named ‘news’ and see different contents because we are on different instances. So you either subscribe to all news channels on all major instances and see lots of duplicated posts, or miss out on some posts.
Yeah there has been much debate going on about that here