Take it from someone that has put the time in getting their own older brother sober after a decade+ of battling alcoholism. YOU, need to let him fail, let his life become unmanageable. Move out. Take care of yourself and stop helping him. The only way his behavior and perspectives are going to change if he wants them to. That won't happen until he sees them as unmanageable and desires to do better. If you stick around managing him, you aren't helping, you are enabling and thus causing no reason for him to improve.
It ain't fun, and it doesn't always leave you with a positive relationship. But if you feel his problem has become that significant than the only thing to do is leave him to manage his own life.
Ask anyone, in any addiction recovery program. Doing what Destoroyah told you to do. Isn't getting him off video games, it's coping with being an enabler.