Some domains inaccessible from Movistar Spain / Telefonica

Is this a general issue, or specific to sites using Cloudflare? From what I can tell from what has been posted, it’s not Cloudflare.

As it’s a weekend there probably won’t be any staff around here and as it doesn’t look like anything with Cloudflare, I don’t feel it’s something I can escalate urgently for attention. Has anyone reached out to the ISP about this?