I read the headline, considered it for a few moments, and the only response I could come up with was "No." Why would I put an OS on a computationally constrain

I read the headline, considered it for a few moments, and the only response I could come up with was "No." Why would I put an OS on a computationally constrained device that is essentially guaranteed to spend a portion of the CPU time doing things I likely don't want done, for someone else (Microsoft in this case)?