If currently if you dont have any CC apps installed.
Run Cleaner tool and remove all CC apps and reinstall Creative Cloud desktop app and check.
If you have installed other apps , just remove Creative Cloud desktop app and check.
https://helpx.adobe.com/creative-cloud/kb/cc-cleaner-tool-installation-problems.html
You may also contact Adobe Support :
https://helpx.adobe.com/contact.html
Click on Chat icon at right bottom corner.
Though none of those steps helped, I'm grateful for the suggestions.
The answer turned out to be this: TURN OFF YOUR VPN.
I'm using SurfShark and have it set for a US location (and I am physically located in the US plus my Adobe CC license is US-based). I have no troubles downloading apps, as I did today. I have no trouble connecting to my Adobe account.
The only trouble is with the 2022 updates not showing in my Adobe CC app if —and only if— my VPN is turned on. Clearly this is either a bug that Adobe engineers missed (why would anyone have a VPN these days?) or else it's something that the software should check for and all the help docs should suggest disabling as a troubleshooting step.
No matter. I'm good now. Perhaps someone else will find this useful.