There is also the question of trust: The best solution should be an infrastructure that is due to E2E not able to read the messages it processes. The problem with this setup is, that you want to communicate publicly and you never know, who is part of your communication. I would advice to use signal or matrix if you need E2E. If not, use either Tor to use lemmy and try to stay anonymous or be aware, that your messages are not (which is always the best approach in my opionion).