I don't think you ought to be punished for his bad behavior, but only you really know if you're really abusing the games or not. At any rate, you still have a job and a marriage and you're not flunking biology, so there's no point really in doing this to you.

My advice as an experienced parent: ground him to his room after school. Make sure you have confiscated all his game controllers. Don't bother to take the console, it's useless without the controllers. Password him out of his computer, if he has one. Strictly supervise "for school" computer use, but otherwise, it's off-limits. Do not allow him to get his fix by watching you play, either.

This way, you aren't being punished for his bad behavior. This is also a really good opportunity to talk with him about why he gave up on biology and what other choices he could have made, and get his input on where he thinks he went wrong. You also have a really good opportunity to show by example how an adult can choose to have the games available and still use time wisely.

But you especially need to address what he thinks is going on with him. Punishment without discussion of what happened here is pretty useless. "All or nothing" bans tend to do nothing but create more resentment and create the will to sneak around and work around the ban. That's not helpful. Also, keep in mind that if you throttle the games, he'll just take up something else to escape into.