Because it sets a very worrying president for the future of computing. This Apple like level of control is the holy grail for monopolists like Microsoft.

They have no market share. Sure, not yet

Don't underestimate just how powerful a draw of having Office BUNLED with the OS will have. It's basically Mocrosoft using their dominant market position in Business software to buy market share for their new OSes.

My personal view : in three years time Microsoft will be the dominant player in the tablet market, closely followed by Apple. In 5 years, they'll have 80% of the market. And Office will no longer be bundled.