[ Edit ] Found your answer [1] Interesting that they dont have a default fallback record if EDNS is not available. Some people (myself included) block it. They should look into Anycast.
Re:Cloudflare is blocking lookups for archive.is
by bifrost on Monday July 29, 2019 @05:07PM
(#20559465)
Yeah, I eventually dug into it and saw the EDNS thing.
I can understand why Cloudflare wants to not pass EDNS but they could also trivially assign a regional but dummy record...
[1] - https://jarv.is/notes/cloudflare-dns-archive-is-blocked/