I think it's the hockey goaltender padding effect. Compare the padding goaltenders wore back in the '60's. No face masks and skimpy padding compared to the equipment worn today. As a result, (maybe?) hockey sticks became more flexible and stronger as goaltenders took more hits to the body.
And then there's the road safety and car safety design. They both allow the bad driver to take more and worse chances as survivability improves.
So all that translates to the cyclists who is dressed in hi-vis protected clothing including headwear. It's not the cyclist taking more risks. It's the driver taking the risk to the cyclist.
After stating all that, personally, I don't think I've experienced any worse. Maybe I don't have anything else to compare with or I'm too scared to ride in dark clothes with no lights or helmet.