Does federation have a bit of a learning curve? No doubt.
Is Lemmy buggy as heck? Absolutely.
But I don’t think that really justifies a lot of the comments I’m seeing in Reddit alternatives threads that it’s hard to figure out. The front page feed and sort options are very similar to Reddit. Searching for same-instance communities is not too difficult. Posting, commenting, and voting are all quite intuitive. What’s the problem?
I’m not sure how federation does anything to prevent that from happening, though. They can still do that on your instance, from their instance.
At most, I suppose an instance could defederate from a troublesome instance that’s doing this, but the more that happens, the more fragmented the Fediverse becomes, and it starts to defeat the purpose of federation in the first place.