Ideas
Akelaphobia, thanks for confirming these were the steps used!
DigitalWolf333 suggested launching in windowed mode. Here is Steam's documentation on how to do that on their platform:
Steam Support :: Using Launch Settings for Video and Display Problems
Please let me know if you have already had a chance to explore that workaround as well, what the results were, or if you ran into any trouble.
Yes, I've tried windowed mode as well as the launch command to force windowed (also -noborder and setting the resolution manually through the same method).
None of them affect it at all, it still always tries to launch exclusive fullscreen at a tiny resolution for a few seconds before then switching back to what I have set in-game.
Also you've combined my reported issue with someone else's when they're not even the same bug. This other person's bug is about the game loading a different resolution after it loads their in-game settings. Mine is about the opposite. Please seperate my thread again.