{New update}
Your method should work now, whether or not you put the file in the data folder or the game folder :)
[Update]
So you're doing the right thing. It should work if you put the file in the data folder. That isn't what I intended, I'll make an update now so that it works when put inside the game folder.
I don’t know about OP, but personnaly, I had created a file called platformsettings.txt alongside the ThatGame.exe file with the contents:
moving=true
But that didn’t work. it’s a bit of an isssue that nothing indicates the format the file should have, or where exactly to put it.
Edit: maybe you could have guessed from the .exe, but I’m running the game on Windows.
Ahh so that's how you do it - I was searching the game files for a platformsettings.txt and didn't find anything, so I thought checking the game directory was a mistake. Maybe adding an existing file with moving set to false would be better? Or state that the file is "missing" in the game? Great game (and video) btw especially for a solo developer in a week.