The main reason I don't use Safari on the Mac is that all extensions (including ad-blockers) require an AppleID (because they have to come from the Apple App store), and I don't want to be forced to tie my laptop to any online account.

If the DDG browser has as built-in good-enough ad-browser, I'll probably try it. Though I doubt it has any practical advantages over Firefox/Edge + uBlock Origin, which I'm using now.