I use a catch all alias that maps all local parts to one account (unless a specific account or alias already exists)

Requires zero user action to make up an address

>Sounds tedious if it’s the former

Thankfully it isn't.

To set a catchall with sendmail, add a line to /etc/mail/virtusertable like so:

   @domain.tld <emailaddress>

And if I decide to block a particular address, which I've only had to do with addresses set up for specific sites (which I've then decided sends me too many emails -- I've yet to receive spam that's not from the site in question), add a line to /etc/mail/access like so:

   To:<specificsite>@domain.tld error:5.1.1:"550 User unknown"

And that can be temporarily (or permanently) reversed by commenting it out. I imagine it's something similar for postfix, qmail, exim, etc.

Edit: I'd add that I make extensive use of folders/filters to handle email as well, so unless I don't want to use a site/service any more, I'll usually create a filter unless I don't want any more contact with a specific entity -- then it's "user unknown" for that email address.

1password started doing this with fastmail, ux is not great as it's not easy to create one manually in 1p but only when you're autocompleting your email on a site, but I guess it will improve over time. https://1password.com/fastmail/

Just a curl command with mailcow-dockerized

I do this but it requires 0 setup, it's a feature in Fastmail.

A catch-all that forwards to one account works very well.