I'd think the conclusion you should draw is not that "even the famous experiments were not valid, so nothing in psychology is" but rather "the validity of an experiment does not correlate with how famous it is".
See also the replication crisis.
Frankly, you made up accusation of academics from nothing and without bothering to check what they generally say. You just made it up
What would be the equivalent of Newton's laws in psychology? Does such a thing exist? Or does the whole field just prove how complicated human beings are by being incapable of proving anything else (which in itself would be an interesting result, don't get me wrong)?
But do we have an example of something that is provably valuable? I am genuinely interested: after reading this article, I realised that there is nothing I can attribute to psychology off the top of my head.
I mean, Milgram used to be one, but well...