Surely this change will break someone's workflow.
Of course I don't have access to usage stats, but I firmly believe there is a long tail of people around the world, who would still benefit from such service. People stuck with 3G devices (for whatever reasons) in locations with 3G service disabled. People on the fringes of meaningful cell coverage.
This change follows the trend of the last decade, whereas instead of striving at catering to everyone at the price of tolerable cmbersomeness, companies, that do have the means to cater to everyone, build their services only for the mainstreamest main stream and the rest is welcome to bugger off. Microsoft leads the pack, apparently inspired by Apple. Google seem to do their best to catch up.
Of course they all are commercial companies and the sole point of their business is to make profit, and one can't ask, or indeed expect, them to keep a service running, which is not fit for this one purpose. My feeling is, though, that slowly the long tail gets longer and longer with increasing pace. I do hope this will open the door to markets seemingly well walled off by the big guns to young, fresh and innovative competition*.
* The competition who will profess the resolution not to be evil at the very beginning, only to slowly ditch that notion, which, in turn, will again open door to competition, and so on and on:)