Brushless or Brushed, same thing as far as the ESC is concerned: the higher the drive freq, the more heat generated by the ESC
That's because the ESC dissipates heat at each MOS switching(switching losses)... 16KHz is 16000 switchings in a second
For the motor, I can't comment, it is not my field. I would love to understand why higher drive frequency is more efficient for the coils, if anyone knows...
