iCloud Photo Stream not updating since turning off iCloud Photo Uploading

So, I know that iCloud photo backup and photo stream are mutually exclusive. Even though you can enable both on your phone, there are plenty of articles stating that your photostream won't work if you enable photo backup.

So I turned off photo backup since iCloud can't sync photo backups to Windows machines, so I'd at least get the photo stream syncing to it. Except... it's not. I turned on photo backup in Feb, and since I turned it off a week ago, nothing else has uploaded. The shared albums do sync, just not my own stream. I've also confirmed it's not my phone, as my iPad has all the pictures taken from my phone.

Even stranger, if I add a photo to the stream on my computer, it doesn't show up in the folder I just added it to on my computer. But it does show up on my iPhone and iPad!

I've disabled & renabled photo stream on all my devices (including PC) multiple times. When I disable it on my PC, all the existing photos & shared albums disappear. I then re-enable it, and it brings back the shared albums, and the photo stream up through Feb.

Any ideas on how I can get the photo stream on my PC to start updating beyond Feb?