Thank you much! Looks like it was mostly for Xbox Game Pass users:
KB5004476 is an out-of-band patch and it is marked as an optional quality update. This patch should be installed only if you’re having issues when downloading games part of the Game Pass from the Store. Since it is an optional update, it won’t download or install automatically.
After recent Windows or Windows Store updates, some users encountered error codes 0x80073D26 and 0x8007139F whenever they try to install games using Xbox Game Pass on Windows. The process simply failed and users were redirected to the Microsoft Store and Xbox app also returned another error code 0x00000001.
Thank you for posting this! 