As I understand it, one of the difficult problems on Windows is the file locking semantics. When a library is loaded in memory it cannot be replaced on disk. So updates require a reboot to put new files into place. This might be the cause of the effect you describe (administrator being unable to delete files).

It has been about ten years since I maintained some Windows installation packages for a reasonably large project (originally built with a proprietary package builder when I took it over from the previous maintainer and then I ported it to build using a fork of the Python MSI builder). So my understanding of Windows package management and the pains of making things work reasonably is weak and out of date. So take this guess with a grain of salt. I might even be describing what happens and why wrong I dunno...I avoid working on Windows as much as possible, so my ignorance is high.

I can really only speak to the comparison of OneGet to apt or yum, which is absurd on its face. And, I have observed the interesting level of denial that kicks in whenever criticism is leveled at an OS based on weak package management. There's always a lot of "well, I just do this ridiculously unwieldy thing and pretend like it isn't a ridiculous and unwieldy thing to do, so I don't see why I would want something like apt or yum". This tread has been no exception. It's like I'm insulting them personally when I say the workflow they are having inflicted on them by their OS is suboptimal.