Migadu has an interesting model of not pricing by number of users, which may be worth looking at if you have 10 accounts but not excessive usage. Ultimately I didn't go with them because I wanted an account that supports second factor.

Edited to add: migadu's pro/con list: https://www.migadu.com/procon/#the-drawbacks-list

Everyone else I know of prices per user. If you just need aliases and not separate mailboxes, protonmail is good.