Ok~. This is how I feel about those details:
Ok, it's small, what else? Do they have something against small cases? Is something broken in/on the case? This is really broad, and only yields more questions than answers.
What the hell is a 'style of gaming'?
Was the PC not meeting their gaming fps target? <- Is that the 'style' they're referring to? First time hearing something like that.
A GTX 960 would be considered low end these days, but the I7-6700 would still be fairly relevant... that combo should be at least 60fps medium, maybe high graphics(depending on the game) at 1080p.
Now, this one, I get. It makes sense to me if it's just taking up space, or they needed to make a quick buck, but - BUT! They also could make more from trying to sell the parts individually.
I would request a visit to see him play a few titles to be sure - or some kind of visual proof that it still works - and no sneaky videos from 3 years ago!