15 year old ds wants to give up activity to play more Xbox

[Nickersnackersnockers]

What would you do?

He is openly admitting he is not going back to his Saturday afternoon activity in September as he wants to just play his Xbox.

He has already given up two activities to do this but wants even more time on it. He is hopelessly addicted.

Yes I can just switch it off but he will turn violent and trash the house.

Does anyone else have this problem?

I would be clear that - whilst he can obviously give up the activity - that he isn't able to spend any more time on the x-box.
If the would turn violent and trash the house., it seems that is even more evidence it has reached a point where it is clearly a major issue, so would be offering the choice between either limiting time on it, or getting rid of it altogether.
The answer isn't to teach him that he can do what he wants because you are afraid of his violence.

Thank you back think I just need to do as you suggest and tell him that he is maxxed out time wise.

It's going to be messy though

Doesn't anyone else have these problems?

You have allowed him to give up two activities already to spend more time gaming, why? Of course he is going to push for more, you have taught him that it's ok, Being afraid of your 15yo is no way to live, it's not going to get any better as he gets older. Reset the ground rules now while you still have some chance.