As for GTA 5 VR, I know they can’t make any money of their work or they’d have something worse than a just a mere DMCA ( Nintendo made someone pay it half his income for life ) but I know the most devs are mostly doing it for the challenge and more importantly out of love for the game. As an exemple, here’s someone porting portal to the N64
I think it’s the wording they used. A DMCA is one thing but skirting around a license is another thing and that’s not what Take Two went after.
I think it really depends on the company and what they think they can get away with in the fine print of the terms and conditions. It might be Nintendo as well who I believe at a time was going after game play videos.
I wonder if there is a court case in the US that talks about game modding in a similar way to the one that legitimized console modding?