Game won't run

[FilthyCasual]

It starts flashing back and forth to black screen and wrong resolution. Have to exit via Task Manager.
The game used to play (last time on Nov 24, 2023)... and now it just doesn't do anything.
Going to try to troubleshoot using the stuff found below, but seriously, why is a 15 year old game suddenly not working for people?

[FilthyCasual]

I did this:
1. run steam as administrator
2. go to local files of COD MW2
3. locate iw4sp.exe (this one is for single-player) and open its properties
4. in "compatibility" tab check the following boxes: run this program in compatibility mode Windows 7, run in 680x480 screen resolution, disable full screen optimisation, run this program as administrator

Now the game just crashes after the first title screen (about 5 seconds in, after asking if I want to run the game in safe mode... it crashes whether I say yes or no).

[FilthyCasual]

So, CoD MW (2007) runs, MW2 and MW3 both don't run.. at all. Not from the desktop OR from steam.

[FilthyCasual]

Reloaded all drivers, uninstalled/reinstalled... and it still wants to open in safe mode, then says that steam must be running... which is odd since I am running it from steam.