@VIcFury this is true, and there's been attempted replications since, though the data is a mess

imho it's not so much that the experiment's results were or were not valid, were or were not true - you're certainly right that this particular experiments data wasn't super useful for that due to systematic issues

but that this study represented part of a larger attempt to grapple with what exactly does authority do to people/how can we organize a society without the kind of cruelty that authority and especially prisons represent. And whether or not anything can be done about organized urban living at the scale of the USSR, say.

Especially considering some of the other things happening around this time - the beginning of nixon's war on some drugs (which increased the number of imprisoned people in the US substantially) -- it was at least an early step in attempting to come up with a better answer than "just kill all the people guilty of $X_CRIME" and whatnot.