> They tried to make Windows into a mobile OS, severely restricting the alowed actions of program

They already had Silverlight! For Windows Phone 7. Then they killed that off too and expected the "plethora" of WP7 apps to be rebuilt for WP8 (requiring the beloved Windows 8 desktop OS for this task). Then they again expected developers to throw that away in favor of UWP for Windows 10, which unified the desktop and phone OSes. By then it was too late.

Old apps still ran on the newer OSes but the SDKs became dead-ends.