Maybe the disparity comes from the fact that, as you stated in an earlier post, men seem to be wired for short-term interactions while women seem to be wired for long-term ones (not true in every case, but as much as I hate to make generalizations, I do think we're more or less wired that way). So while a woman often seeks a long term relationship, she meets men who are only looking to get laid. However, that's not always obvious up front. I've met toooo many men who say all the things they believe a woman wants to hear in order to get what they want. They play the part of the guy interested in a long-term relationship so the woman will feel like she's met her match. But too often, once he gets in her pants, the fun's over. Challenge met. He loses interest and the woman is left with a bruised heart and kicking herself that she didn't see through the guise. And from my POV, guys are getting better and better at this deception. Online dating paved the way for that. That's mostly why I say there seems to be a shortage of good guys out there. You might have all the qualities I want in a guy, but if you deceive me, you're not a good guy in my book.
Another reason women complain about "no good men" is that too many men lead with the sexual angle when meeting online. Some think the way to a woman's heart is through their penis. And, I don't want a guy I don't even know asking me my bra size or if I do anal. Sorry, dude - that's classified at this point. You don't have a need to know.
Now, to be fair, from guys I've met, I know there is deception on the other side too. But I only know that from what I've been told. And I'm well aware that women do the same thing with pix. But if that's the foot (or boob) they lead with, they can't then claim that the guy led them astray.
I don't play that. When I meet a man, I'm up front about what I'm seeking. He can't come to me later and claim any different.