Since launch, Treyarch has been rather generous when it comes to updating Call of Duty: Black Ops 4 via server-side hotfixes. While most of the time it goes over without a hitch, theres bound to be an instance where it might show Black Ops 4 game settings stuck screen.
Source: N4G PC Call of Duty: Black Ops 4 Game Settings Stuck Fix Outlined and It's Super Easy