icloud.com site has stopped loading anything - 'Cannot Load Library' for Photos, etc

Does anyone know what one can do to 'kick' the icloud.com website into working once it stops working for you?

I can see my Photos, Drive etc on my iPhone and iPad, and my 50gb plan is currently less than half full.

But the icloud.com website is more disheartening -- I'd like to pull some pictures from it (for a zoom bg on a different computer), and I can log in and see the 'home screen' with the little apps just fine, but clicking into any of them -- Photos, Notes, Drive -- gives errors, probably all related.

Tested in Safari, Chrome, and a new Incognito Chrome window.

Specific example: Photos

• icloud.com/photos - when reloading this url specifically, a spinner for about 30 seconds, then 'Cannot Load Library'
• I see one failing request, to: https://p17-ckdatabasews.icloud.com/database/1/com.apple.photos.cloud/production/private/zones/list? ... with a bunch of querystring params that probably have personal tokens :)
• it seems like all other requests, including ones that verify my client (even though one takes 30 seconds to complete), are successful.
• But when it tries to load a list of contents (at the url mentioned above), in this case apparently a list of things that have to do with my photos, it fails, and I see a JSON response to that request that has {uuid, serverErrorCode: "ACCESS_DENIED", reason: "private db access disabled for this account"}.

If anyone's had an idea of how to fix/work around this, let me know. I did see that some of the requests seem to be located to a specific area of the country, so maybe there are datacenter issues where it's expecting my stuff to be present in a certain datacenter and it's not? Would go with what some others mentioned in a similar issue I saw, where icloud.com didn't work on Wifi but did if they hot-spotted to their phone.

Let me know if anyone has any ideas. :)

No need to post a link to this https://support.apple.com/en-za/HT205966 KB article about the Mac Photos App; I saw multiple people post links to that article on other similar issues, but this icloud.com, in a web browser, so that article is unrelated.