I switched like 50% to a domain/email provider with my own domain. They offer a webmail interface for it but I just use it in thunderbird. It costs 2€ / month, 2GB included. Spam filter works fine.
Not a single compatibility issue since the beginning (4?5? years)
Setup is easy, and my mails are stored in germany respecting all the laws.
I use strato for this, and for mails they are fine, if you want to do anything else with the domain, use someone else, like Ionos.