Hey there Paul,
Thank you for your prompt reply. I checked through the link you sent, no dice. The Microsoft Store says I own the games, but it won't let me install it anywhere but my Xbox. When I go into, for example, Fallout 4 Game of the Year, a game I own and purchased 5/14/2018, it says that I own the game, but not on this platform, that being the PC. I can provide proof of purchase in the form of my Microsoft Store order history. I understand that physical copies for Xbox games won't work on PC, for obvious reasons, but what bothers me is that I apparently can't play the Xbox games I bought on the Xbox's store, the very same store I am using on the PC.
Btw, my Windows 10 version is 1909 (OS Build 18636.836)