Open up the Windows settings menu, find the "Gaming section" (The one that has the Xbox logo), go to Gaming mode and disable the only setting there if it's on.

I tried the mod that supposedly fixes the cursor appearing on the screen, but it did personally nothing for me, until I disabled that gaming mode.

The game will still lock out for opening the Steam overlay and alt+tabbing, BUT you can unstuck it finally by just opening the menu by pressing tab and exiting it, then click the right mouse button to once again move around. Make sure you're not on the Nomad or else you cannot unstuck yourself with this.

Certainly beats restarting the whole damn game, especially if this happens in a main mission where you cannot save manually for some odd reason.