Which is good. You either have an open system or a closed one. There's no in-between.
If you want to have advantages of public free decentralized network you can't obfuscate and centralize bits and pieces of it. Also, it's 2024, we need to stop this misinformation that email address is supposed to be private. What is private is email address association with the owner and Lemmy doesn't leak or infringe on. The address is literally called address because it's supposed to be public.