This seems like a tricky thing to find, as I primarily see this on 4chan (who doesn’t keep records (disregarding 4chanarchives, which you should look at to see if there are any of those threads that were archived)).
Otherwise, to show proof, I’d look for blogs on the web (a long shot) or just look for threads on 4chan and screenshot them.
As for when threads about ask a X anything started, that’ll be the large problem. If you can narrow it down to year, it would be a start.
God, I really am bad at helping, I’m just restating problems.
Anyway, if I find anything helpful, I’ll report back here.