Really. I am the driver that leaves a gap between me and the vehicle in front so idiots can overtake and have somewhere to go rather than pulling into my side. I bet you don't. I doubt if you have ever thought about it.
You said it.
I bet I don't
Its too long because of the idiots that drive too fast. I have never seen one where its too short.
Its not a problem for good drivers, we don't go into the backside of speeders. Not even the ones that overtake, pull in and jump on the brakes at the speed camera they have just seen.