[mgamache]

Some is probably due the codec VP8 vs h264, but they are not wildly different in efficiency. WebRTC doesn't use VP9 or H.265 yet. I view the higher bandwidth used as an attempt to maximize quality at every bandwidth they just didn't set a ceiling on the encoding frame size. It pushes the total quality number higher on the chart they've published.

[pishpash]

As a practical matter it isn't very, well, practical to have to change every codec to support this. Maybe in the next standards, but that's going to be hard.