There are plenty unfunny guys who think that shit is funny.
There really is no shortage of unfunny men.
The only real difference is that nobody hits you over the head for finding them unfunny as fuck.
For women you have an audience that is ready to pretend they're funnier than they are for political reasons, or is inexplicably convinced that "hee hee, my genitalia do gross things" is the epitome of humor.
However, there is only limited public interest in such a thing and it gets boring quickly, so movie productions based on nothing but this brand of barrel-scraping humor have failed with the regularity of clockwork.
This is not to say that women can't be funny, or that being raunchy is bad, but you need genuine wit behind this kind of thing.
There is a reason why guys don't go on stage and make jokes about the particular workings of the prostate.
If more than half the audience has only a vague idea at best of what you are talking about, you have to explain, and then you're not funny.
Or you lose the greatest part of your audience because nobody gets the punchline.