One thing that tends to gravitate me back toward Gmail is that I’ve piped now two decades of email into there and the search on Gmail I find quite fast and good. I search for emails from years and years ago all the time, at least weekly if not daily.
While other apps have lured me away, I find they do so via really nice UI and flows for incoming email. But they don’t do much for search. It’s either slow, not as comprehensive, or both.
I’m afraid I’m not terribly technically saavy about email in this way. Could I and should I have an offline backup of my entire email archives? Could a local email client, like Mail.app, do that for me such that the search in that native client was as comprehensive as the web Gmail client?