Shocking news everyone!  5GHz-capable wifi devices are faster than 2.4GHz-only wifi devices, even when you plot it by device model.

(I don't know why some specific device models seem to show a mix of 2.4GHz and 5GHz capable features.  I think we might be mis-detecting it in some cases.  2.4GHz-only devices reliably show up only as 2.4GHz though.)

The most common device type is "unknown."  Oh well.