Example: around the end of June this year the mirrors.kernel.org infra was failing to sync (DNS issues of some sort) the latest content, so your upgrade would appear to have no new packages because the stale content was a valid repo, when in fact there were many updates and other mirrors were in sync.
According to what I read in their main page https://cloudflaremirrors.com/archlinux, they seem to be caching the packages from mirrors and serving it via their anycast network.
Alternatively (/ realistically), perhaps CF would prefer the value-add of rerouting where there are newer packages instead of the singular approach of geo-routing. Definitely let them know.
I'm seeing multiple comments in this subthread, I'd apply the 2nd line above to everyone affected, if a bunch of people let CF know maybe they'll figure something out.