I got a DUI in my early 20's. I was right at the line of the legal limit. Lost my license automatically for 6 months along with a $525 fine, went to court and got sentenced to another month suspension, an anti-DUI course, and an evaluation as to whether I was an alcoholic (I'm not).
It slowed down my drinking and I was definitely more cautious about using designated drivers afterwards. And if I was driving, I'd limit my consumption and wait before driving. For example, I might have a drink at a friends, then switch to water and wait a couple of hours before driving.
I do think the laws are one-size-fits-all, when in reality your ability to drive is based on a lot of factors. All we do is judge a certain blood alcohol level as intoxicated. People react to alcohol differently. I've seen people have one drink and start acting goofy. I've seen others have a single drink and it doesn't seem to affect them in the slightest, even though they're of relatively the same size and build. It isn't driving, but I know a guy who gets better at playing pool the more he drinks (at least until he gets fall-down drunk).
Sober is the safest. But I would rather drive in a car with some people I know who are at the legal limit or even above it than drive in a car with others I know who are perfectly sober.
We had a guy at our hall who was practically blind, but still drove his car. It's a miracle he didn't kill himself or somebody else. And many people who had driven with him never did again.
Equal to the hatred for drunk drivers should be hatred for the old people who are no longer capable of driving safely, but do. Or people who are distracted by talking on a cell phone. Or people who text while driving. Or people driving tired or sick. Or people who just plain never learned how to drive safely.