I already switched years ago to Mac. Even Apple didn’t make such a bold/foolish move as forbidding 3rd party app to run. If Windows takes this road no problem for me, erasing my bootcamp partition* and installing Win 7/8.1 would take a few hours and problem solved. But that would be a real problem for non technical people doing real work with their PC.

* which can be booted in VirtualBox from OS which is the way I use it most of the time.