I don't think it's so much about the timidity of the driver, it's the effect on driving slow has on people behind you. Driving below the speed limit increases the amount of drivers who need to do overtaking, which are moments substantially more dangerous than just driving straight. If it weren't for forcing other people to overtake I don't think we'd really care, even if it was a sign of timidity.
Very common to see older people drive slow on the highway because going 100KM/h seems scary to them. This is, of course, absurd, since driving 80KM/hs on a 100KM/h road causes way more moments for bad things to happen because you're forcing everyone to merge into the speed lane, including trucks with bigger blind spots, rather then only the drivers choosing to go above the speed limit. If you do this you should absolutely be fined, and that's not because it's a good metric for timidity (which I agree can be bad for drivers in general), but rather that the action itself causes harm.
Very common to see older people drive slow on the highway because going 100KM/h seems scary to them. This is, of course, absurd, since driving 80KM/hs on a 100KM/h road causes way more moments for bad things to happen because you're forcing everyone to merge into the speed lane, including trucks with bigger blind spots, rather then only the drivers choosing to go above the speed limit. If you do this you should absolutely be fined, and that's not because it's a good metric for timidity (which I agree can be bad for drivers in general), but rather that the action itself causes harm.