It's management instinct to want to see people. IF they can't see you, I think they feel that maybe you're slacking off. (Of course, the manager never sees you when you write a bunch of code in the middle of the night because you didn't get any real work done in the office.)

These changes, particularly in the Yahoo case, reflect poorly on those managers in my mind, not on the concept of remote work.

The ideal programming environment is effectively remote- every engineer in their own office, with multi-party audio or video (e.g.: google hangouts) for collaboration.

If your primary cost is engineering staff, why would you make them %50 less effective when they're working and on top of that take 2 hours out of their day each day for a stressful commute?