IMHO there was more responsible driving when we had few speed limits. When I learned, there was no open road speed limit and just one in-town speed limit. Every driver had to decide what was safe for the conditions. If you got it wrong, Mr Plod could charge you with "speed dangerous" or "manner dangerous". Now there are varying limits everywhere, and most drivers take them to be the mandatory speeds for driving that segment. Thye drive to the limit regardless of conditions. I know when I say "slow down a bit" SWMBO replies "Its 80 here" and ignores me.