Mozilla is becoming irrelevant in modern market and their response seems to be to blame others. I had guessed it when they fired their CEO over some ridiculous issue.

Windows is bigger does not mean they have any obligation to give space to others. Does Apple let you install YouPorn App on your iphone ? Does Google let you replace default search with Bing if you want ?

Both Android and iOS are immensely successful and both are on tight leash of Apple and Google. The reality is that, that tight leash has made user experience much much better. My father likes to surf net on his Android phone because his laptop is full of Ask and Conduit toolbars and he has no idea how they go there.

The world of Internet is now enough complex that it pays to let one company keep everything on tight leash and Microsoft's move in that direction makes a lot of sense.