This right here. And a hosted suite of productivity tools that have documented, public formats that contain all of your data (and not just a link to the cloud-hosted copies).

Amazing that GSuite's only real competitor in 2020 in Office365.

Would you consider Zoho a "real" competitor?

https://www.zoho.com/

Would a Nextcloud instance work?

I've checked out Nextcloud a few times, but it really needs a sizeable and trustworthy brand that would host it for you, allow you to point a custom domain at it, and provide zero config email/calendering out of the box.

I'd trust Mozilla.

I second this wholeheartedly. I would be happy paying at least the $5/mo that they're charging for the VPN to have web-based access to privacy-respecting email service tied to a name I tend to trust like Mozilla (hopefully with a fairly vanilla domain name that doesn't get weird looks).

Purism's Librem One suite [0] comes the closest, but I just don't have the trust in them that I'd want before pulling the trigger. They have a history of making grand claims with sub-par delivery, which just doesn't cut it for a service like a primary email provider. They've claimed plans to add features like file storage for ages now with no updates. Email is just too important a part of daily life to risk it.

[0] https://librem.one/

I've heard good things from HEY[1]; I've been thinking about using their trial

[1]https://hey.com/

Hey looks great and I trust it will be around for a while. Unlike inbox from Google.

I would 100% sign up for hey if I didn't migrate to Fastmail this year.

Unfortunately it's invite-only, at least for now.