Yeah if default settings, mullvad is probably hard to beat if tor is off the table.

Firefox sync is E2EE too (or at least can be, mine is)

With apple you’re limited to 5 sending addresses per domain, so no I cannot reply as the from address to most, but that hasn’t been an issue for me at all.

Depends on your use case. I went with using a custom domain with my iCloud mail account. This lets me accept all messages sent to my custom domain.

So when I create accounts I just use that as the email address like this: lemmy@customDomain.com, bsky@customDomain.com, etc.

They all go to one mailbox but that’s all I need anyway. I’ve been happy with it.