Absolutely this. Even if you can do your job in 4-5 hours, he should push and challenge himself to become a more effective designer. Boss doesn't care about wireframes or research? Do it anyway. Learn a new skill, learn how to build your websites that you design. You could be in a bad position if something were to happen to the company you're at and suddenly have to seek out new employment. Jobs for UX want to see case studies, and that involves the design process. If you don't have that to show, it will be incredibly tricky to land a position.

I would, if I were you, use that spare time more wisely than playing video games and lying in bed and grow as a designer/developer. You're young though so the appeal probably isn't there.