One problem is that the correct answers have to change over time and SO does not account for that except by having drive-by downvotes from dweebies who have no business even answering questions.

I used to answer questions on SO, but got so tired of arguing with idiots that I decided it wasn't worth my time anymore. It's too bad, too, because I strongly believe in "giving back" where I can and SO was a way to do that. No more. I still google for answers on there all the time, though.