The game just refuses to run - crashes every time before it even starts

I bought the complete edition from Steam, when I launched it for the first time it connected my steam and rockstar accounts. The game keeps on crashing even before reaching the rockstar logo or the first menu - and without any error message, annoyingly enough. it crashes right after the first black splash screen.

Here's what I tried (and failed to work):

  1. Re-install the game multiple times. Validate the files multiple times.
  2. Installing mods that should resolve some bugs (FusionFix/DXVK). Removed them after it didn't help.
  3. Run the Steam and/or Rockstar launchers as administrator.
  4. Tested some launcher options command lines people suggested online.

Still, the game crashes nonetheless before the menu even appears. Anyone encountered anything like that?

Also - oddly enough - the game runs fine on my Steam Deck. it's my main machine where I'm having this issue (RTX 4080 SUPER, 64 RAM, i9).

Any suggestions before I ask for a refund...?