Both auto-forwarding and auto-reply are paid features, which makes cancelling & switching much more difficult. Gmail is a breeze comparatively. I highly recommend against using their addresses (e.g. protonmail.com, proton.me, pm.me)
Email forwarding is available for everyone with a paid Proton Mail plan.
(source)
Reminder of this:
https://poolp.org/posts/2019-08-30/you-should-not-run-your-mail-server-because-mail-is-hard/
And that mailu.io (and other similar projects) makes self-hosting email almost trivial 😁 (at least for people that can run a pre-configured
docker-compose.ymland buy their domain etc)