I’m refering specifically to:

This omits FET+1 and FET+N+1 drivers. Which are not efficiency queens either but are significantly better in their regulated modes than he states. In this regard - it is misleading but it is not incorrect.

However it is incorrect w.r.t. higher, FET-only modes of BLF-related drivers.

As maukka’s scope shows, in PWM mode current is lower than with FET wide open. That’s because something (which TK expects to be a resistor) slows down current rise and fall, reducing peak height.
Yes, FET, FET+1, FET+N+1 drivers are not really efficient. But not as bad as he stated.

Sure, a FET driver can kill a LED. We’ve had such failures even in production lights. That’s not what I referred to though.