I think Microsoft may be wildly underestimating the amount of goodwill this sort of thing costs them. Windows has been steadily losing ground to OS X, Linux, iOS and Android, and a big part of that is its reputation for being the platform stuffed with ads in places they don't belong. (Because of malware and OEM crapware, mostly). What happens if you're an OS X user considering switching back, and you look over someone's shoulder and see these ads? You conclude that Windows hasn't escaped its terrible past.