Just to be clear, I think registration applications are necessary for anyone without a team of admins across the world.
I’m not saying these instances requiring applications are doing a bad thing. Just that it’s a barrier to entry and given the non-commercial decentralised nature of Lemmy we will never be able to hire thousands of staff to handle reports like Facebook does.
It’s a new problem requiring a new solution, and while I think Mastodon hasn’t solved it yet, I think they are ahead of Lemmy.