This also highlights a difference in sailing high speed boats. I'm doubt you would survive hitting the water
and then getting towed beside the boat
at 20 knots. I read of a singlehander that fell off a tri going 30 knots; snapped a good tether (4500 pounds), which almost certainly resulted in fatal injuries. There are times when you simple must not fall.
I'm not suggesting tethers are not needed. They do use them for certain things. Obviously he goofed. But I suspect it is better that he fell in the water
, under those conditions, than got towed. You would need a tether that kept you out of the water.
One size does not fit all.