I've decided the best course of action would be to just try to get him to see the consequences of his actions, and show how people do when they don't try to play videogames 24/7. I might find a way to artificially make him see those consequences, but deliberate attempts just makes him shut down any sort of contact with reason or reality.
I can write a script, fully open-sourced to disable games of your/parents choice. This will make it so any game he tries to play that is blocked, will require a password of your/parents choice.
Sorry I didn't respond earlier. I was considering your idea, but I realized just cutting him off would make things worse, as he will remain stubborn and maybe get worse. Trogtor sums it up nicely.
However, thank you very much for your offer. I will certainly keep it in mind in case I find the current method doesn't work.