It’s not a recent thing, it’s always been that way. Something to do with the way archive.is and mirrors have their DNS set up.

If you are mostly doing things from home, set up a pihole server with unbound on it.

That way you are no longer depended on anything other than that server and the root servers, så no DNS blocking.

I dunno, I use Mullvad DNS and they resolve fine for me

I think that they block detected VPN’s. Been happening for a while for me using Proton every now and then, but recently started happening a little more often than before.

Definitely resolves on quad9.