The following recent question has attracted a fair amount of comments with anecdotal personal evidence about if and when the expression in question was originally used. There is even an answer based on such personal evidence.
I understand that statements such as the following may sound entertaining:
Yes, I'm sure that I heard that expression in the '70s, or in the '80s....sorry, my wife says it was in the '90s....so it must be the '90s.
I guess it was in Dallas where I first heard it used, or..wait..no, it was San Francisco, sorry.
but, if questions and answers are meant to be useful for present and future users, I think that considerations based on nothing else than personal memories should be avoided and possibly removed,
and while it is true that dictionaries tend to give dates about first usages which are later than actually spoken usages for obvious reasons, I think that the two quoted dictionaries are reliable and the dates that they suggest are to be taken seriously, unless written evidence that proves them wrong is produced.