While I didn’t care too much about all my email going to a google system Ive definitely been looking for an alternative lately.
Two things I didn’t expect was a better web UI and better spam filtering. On top of that I can write to human support and they are both responsive and seem knowledgeable.
For what it's worth, I self host a few e-mail servers and modern Roundcube is actually a pleasant experience, even if I like connecting Thunderbird directly.
Here's the mail server I like: https://github.com/docker-mailserver/docker-mailserver
I still very much rely on some cloud vendor e-mails for uptime and deliverability, though. Otherwise, with random VPSes you risk the IPs having bad reputation or having a plethora of issues (such as some providers not allowing e-mail ports).
Also, in most cases, the other end an email isn't a gmail user but a corporate bot. So Google may actually not have all your emails if you move away from it.
I suspect they share data with a belligerent with its murder victim chooser algorithm, so you might drop "digital".
At least Microsoft and Apple have some identity with Tim and Satya.