I've only seen a couple of those movies - but the first version of King Kong with Fay Wray as the actress, in my opinion, treated her like she had no brains. Come on, the woman didn't even start to get worried that the natives were tying her to a SACRIFCIAL ALTAR until Kong was about fifteen feet away. Excuse me? I also thought it was a bit... condescending? that the woman was the one who "defeated Kong," or was the bait... the whole "'twas beauty that killed the beast" bit was almost reminiscent of old Disney movies were heroine could communicate with animals by just singing a pretty soprano trill. Because the ninth wonder of the world killed everybody except this attractive actress? Uh. Huh.
But Psycho... what a change! First, we have the woman as a villain, stealing money from her company, having an affair outside of marriage , being generally seductive to Norman Bates. Then you have Mrs. Bates, again, having an affair outside of marriage , and the whole thing about Norman being in love with her and keeping her body preserved, going so far as talking in her voice to keep up his delusion. "Her" ending soliloquy about Norman trying to place the blame on her... and that last shot of the overlay of the preserved mother over Anthony Perkins's face is brilliant.
The main difference that I see between King Kong and Psycho is that people were willing to stretch the roles of women in horror movies. Of course, that speaks to the time period that the films were made in, the Production Code and such. So yes. Hope that helps.