iCloud Photo Upload for Windows stuck on uploading photos

I am using Windows 10, version 20H2, and have iCloud for Windows installed. iCloud's Photo Upload feature is currently stuck trying to upload my photos to the iCloud service (Windows is telling me the status is "pending upload"). I have verified that 1,875 of my photos have already been uploaded yet my total amount of photos is around 3,700 (iCloud's photo upload status has not changes since early yesterday morning). It is not a capacity issue, since I pay Apple for 200GB of iCloud storage and my photos take up 32GB of space.

I have read, on Apple's Support forum, that this issue has apparently existed since 2015 with no lasting solution. I have read some "conspiracy theories", on Apple's Support forum, that claim Apple intentionally inhibits Windows users - I'm not interested in "conspiracy theories".

What steps should I be taking in order to resolve my iCloud photo upload issue? Any help will be appreciated.