There are some scientific facts about humans that you can establish because you can do a replicated, controlled experiment and there are others that you can't, for ethical (no one should allow this experiment to be done) or material reasons (this experiment is very easy to conduct assuming you have multiple copies of the planet earth).
If these elements of human behavior cannot be confirmed by replicable experiments, what chance do we have of knowing about it. Claims about such behavior are nothing more than stories, for they are not based on evidence.
> There are some scientific facts about humans that you can establish because you can do a replicated, controlled experiment and there are others that you can't
There is no such thing as a 'scientific fact' that cannot be established by a replicated controlled experiment. The stated dichotomy is really important though, and one that it seems psychology has partially failed to make. For it lost its reputation by presenting 'stories' as scientific fact.
That is not to say there is no value in studying human behavior that is beyond science, but we need to realize that we cannot treat the result of this as 'scientifically true'. Instead, it is something like 'intuitively true based on anecdotal experience'.
So, I don't think thats the real problem. I think the main real problem is that in the failing fields they look for differences between groups while in the successful fields they look for "universal" rules.