If you wish to ask if it started in the past and it is still happening today, the present perfect seems to be the right choice:
"Have women have been treated differently from men throughout history?" is just an example.
Or "Have women and men often/as a rule been treated differently?"
I've read your other posts, but style is not my strong point, and then I'm not sure I fully understand the sentences you posted. But there are people here who are simply great when it comes to style. You could look for "womanfu". She often posts to the "Writing World" section, and I think she gives very good advice to people.
Anyway, I can give this a try. But rememper to ask for a second opinion, please.
"Postmodern feminists argue that the argument ‘most crime is male crime’ is a male’s concern; women should study the reasons behind that women are harmed by a whole range of processes."
All I can say about this sentence is that it has a grammar mistake.
Instead of “the reasons behind that women…” you could say “the reasons why women…”
Again, you’ll surely find someone better for the style question.
"Another limitation of such explanations is that, we should expect far more women than men to be criminally involved, but reality proves the opposite."
I’d start by removing the comma placed after “that” in the original sentence; it really doesn’t belong there.
I would rephrase the sentence as “Another limitation of such explanations is their veracity. Although they suggest that we should expect many more women than men to be involved in crime/s, reality proves those explanations wrong (or "reality shows that those explanations are not accurate")."
I’m sure there are better options, and I hope you’ll find someone with a better writing style than me soon.
Miriam