You take a statistical outlier, apply a metric like pay/productivity, and then tie that to the minimum wage, and make a moral statement that therefore, it should be at xyz level today.

That seems like tortured analysis. If you take 1989 which was 20 years after your date, the minimum wage adjusted for today would be $6.78.

And there is no reason whatsoever that pay has ever been or should be tied to productivity. Humans haven't evolved to become better or faster or more adept in a workplace. We have technology. I don't see why I should pay employees more than before because simply because I also invested in some technology that makes allows them to get more work done with less effort. I see no logic in that at all.

1969 is not a "statistical outlier." It is the high water mark in terms of policy. Lawmakers chose that in 1969 the minimum wage would be set to $12.21/hour (in current terms). We've seen eroding of the minimum wage due in part to worker-hostile politics ever since then (including in the 1980s).

"Humans haven't evolved to become better", and neither have CEOs, even though their pay has soared.

As far as "should," yeah, I think pay ought to be on that level. I think it would probably lead to faster growth.

The only tortured analysis is the idea that workers, who are trained for and use more advanced technology, should not get paid according to the productivity they bring in, but their bosses (who didn't invent that technology) should. There's no logic there, either. It's just bargaining power. And if you (as a--hypothetical?--employer) see no reason whatsoever that workers should be paid more when their productivity is higher is exactly why we need a minimum wage to require it.