Mozilla has irreversably damaged their reputation in my eyes, but Firefox is still widely supported.
I run my own mailserver using mail-in-a-box precisely because libre-friendly mail providers charge for aliases. That doesn’t obscure my address, but it does provide unicity.
Duckduckgo has a free and paid tier. You make an email ending with “@duck.com” and they forward email to your regular address after stripping out all trackers. I signed up but havent used it as yet.
Firefox Relay is more along the lines of what I’m looking for I think, similar to Fastmail. I don’t really like Mozilla after the whole Gab/Dissenter thing, but I will consider it.
I don’t mind paying, as long as it’s not more than a couple dollars a month. Because really all I need is an unlimited number of aliases that can forward to a primary address.
you could checkout tutanota. its less of a private redirect and more just a “normal” web mail service, but it allows you to create accounts with no fuss, where other webmail providers require some kind of secondary email / phone verification.
The free tier is well… free… but they ask you limit yourself to one account (but theres no real enforcement). If you do make multiple accounts, consider throwing some $$ their way, its a cool project. They support anonymous crypto donations as well.
I use one as a spam email, and another as a seconday alias for when dealing with vendors and stuff that i don’t want filling up my primary inbox.