Even after hours of installing third party tools I never heard of before from the internet (secure thing to do right?) I still get a occasional ad to my (single purpose and only Windows) desktop and still each time question why and how anyone would think that's a good idea, or a good place to advertise.

On Windows 10 there's a way to change the license to "Enterprise" (in the shady corner of GitHub), and then you can apply policy to not have it show shit.