I use gandi.net. It gives me all the aliases I want for free. Other services I've investigated are better in some ways but are stingy about aliases. I understand about differential pricing and how it might make business sense to charge a premium for perqs that cost nothing to provide, but even if I were to self-identify as a rich person, the top tier on proton mail, for example, has a limit of something like ninety aliases. Barely a week goes by that I don't need a new alias for some business or institution expecting a permanent irrevocable claim on my attention, and when I printed a bunch of business cards, I put a different alias on every card in case a prospect's contact list were to get leaked to spammers.
> coming up with a domain name is hard!
I use [1] for pronounceable made-up names. It hasn't been updated in a while but is still working fine for me. With patience you can get words that sound like undiscovered chemical compounds, aristocratic dynasties, exotic circuit fabrication technologies, science fiction planet names, ancient goddesses, dystopian megacorps, etc..