Endless "loading Adobe fonts" in the Creative Cloud app? Possible solution below.
After migrating from an intel iMac to a new M1 iMac, I had the spinning/never loading fonts issue in the Font section of the Creative Cloud app.
I tried using the web version of Adobe's font management to deactivate all fonts. (That didn't solve it, but I mention it in case it's part of the solution.)
What eventually solved it was going and getting Adobe's Cleaner Tool:
https://helpx.adobe.com/creative-cloud/kb/cc-cleaner-tool-installation-problems.html
and removing old versions of Adobe programmes. (Turns out there were some remnants going as far back as Creative Suite 4!).
I had the luxury of not worrying about losing older versions because they're still on the Intel iMac, but if you're wanting to keep more recent ones, you *may* only need to delete the much older versions.
For instance, Illustrator 2021 is glacial on the Intel but 2020 is good, so I was mostly working in 2020, hoping that at some point 2021 would get an update that would make it less of a dog. (FWIW, 2021 running M1 native seems pretty damn smooth!)
After using the cleaner tool, I downloaded the latest Creative Cloud desktop app from: https://creativecloud.adobe.com/apps/download/creative-cloud
And ran the installer, which I assume overwrote the Creative Cloud app I had.
That was the point where the fonts panel was actually working again. There is an option there to activate "previously active" fonts. So it was pretty easy to restore them (and probably not a bad thing to cull some of the 380+ fonts), or just activate as needed if updating old projects with certain fonts.
Hope this helps someone.

