There are a lot of smaller providers (but not fly-by-night, like dreamhost and 34sp which both have >20 years record) which will give you a domain with up to e.

There are a lot of smaller providers (but not fly-by-night, like dreamhost and 34sp which both have >20 years record) which will give you a domain with up to e.g. 100 emails for $5-$10/month, which is significantly cheaper than gsuite or fastmail. Another good alternative is migadu (who sponsored the webmail you linked above, and IIRC are already using it). They do charge about $20/year for a micro plan that lets you have any number of addresses and domains , with some throughput limits, and $90/year for a full plan without those limits. Something similar to the micro plan was free until recently - personally, I'm on the $90 plan with a few domains and emails, which would have cost about 10 times on much on gsuite and fastmail.