ETA 2: All these problems were caused by what I had saved in my Library on
Mods.Bethesda.net. I had just been playing with that website to see what was available, I had no idea it would affect what was installed in-game. And prior to U47, it didn't.
I have now cleared everything out of my library and bookmarks on mods.bethesda.net. But my (totally unnecessary) game re-install has yet to finish so I can't confirm 100% yet. This has been exceptionally frustrating. So much so I suspect I will cease messing with add-ons, and cease being a resource for my guildmates and friends.
ETA: Updating as I find more issues.
I have two accounts, one with ESO+/Playstation+ and one without. Because cloud-save requires PS+, this No+ account doesn't save data (including add-on settings) to the cloud.
Before this morning's update, I hadn't changed my add-on settings for a week or two.
I logged into the No ESO+ account first today after the U47 update and my add-ons were fine. But as soon as I logged into the ESO+/PS+ account, my add-ons were messed up.
Specifically, an add-on I have installed in the past, but did NOT have installed yesterday, was installed and enabled. (MemoryUsage).
In addition, two add-ons I have NEVER purposely installed was indeed installed and enabled. (Tamrielic Build Archivist and Circular Votan's Mini Map. I do have the square version of the min-map installed.)
And under Options -> Add-ons -> Installed Add-ons, add-ons I have used in the past but am not using now are listed. "Installed add-ons" should only list currently installed add-ons, right? Not every add-on we've ever tried?
I also had some incorrect libraries, but I suspect that is because I hadn't updated any add-ons in a week or two.
I did not manually download or upload my saved data. What the playstation did, it's not confessing.

This seems like it be a one-number-off bug?
No harm done, it took me a few minutes to track it all down, but all good now.
@ZOS_Kevin