No doubt it was some combination of lower power, physically larger or simply more prone to failure. Do you suppose the designers go to the trouble of a cool-down timer just for the hell of it?
I always use Reverse Hanlon's Razor, so I suppose they do it in bad faith. /s
Actually I guess they both shave off weight/cost and design for built-in model first (that are naturally more heat-constrained) and make standalone variant as an afterthought.
