Windows8 and Windows Phone are different OSes and cater to different needs. Problem is Microsoft tried to have unified look between the two which failed big time. Android is catered to phones and tablets and has zero usability features desktop computer needs kinda like Windows Phone, but Win8 is aimed for desktop PCs.
I think you have the implications there backwards. It doesn't matter for software compatibility if Win8 looks different from 7 which looks different from 6 etc while binary compatiblity stays. Apple on the other hand is well-known for obsoleting parts of both iOS and OSX so that you're forced to update (or abandon) all your software after two cats. It's not that far when Blizzard dropped support for OSX 10.1 through .4 or .5 in MoP while on Windows side it still works on 15 year old OS just fine.
Companies X, Y and Z thought Win8 would change the way they do business and did a rant based on early beta you keep linking around. None of those fears became reality with the final release and those people turned out to be fearmongers and doomsayers. It's not only obsolete because it's old, it's both old and wildly inaccurate. And you somehow still think it's somehow valid criticism towards Win8.1 today?