Many of the most famous 2nd and 3rd wave feminist luminaries are misandric as well as anti-sex (Dworkin comes to mind), and this is often transparently obvious when reading their writings. I fully support the concepts of first wave feminism, including a right to free and safe abortion. However, that doesn't seem to buy a cup of coffee in the cafeteria of second wave feminism (some of whom may even be anti-abortion), whereas my possession of any legal photo of a woman useful for masturbation fantasy would be grounds for being banned from the vicinity. One 2nd wave feminist friend of mine told me that even the mental thought of a woman during masturbation would be immoral, unless the thinker had gotten permission from that particular woman to think those those thoughts first. She was ardently anti-Christian, but the idea that such thoughts can be immoral sounds awfully Pauline Christian. So left and right conveniently come together when it comes to women having monopoly control over men's sexual fantasies, which means ultimately men's sex itself.
If you think women on the left are "loose", that is the opposite of my experience. For greater enjoyment of sex, I have often wondered if I would have had lots more sex staying Christian and Republican. I suspect one is more likely to find a sex parter at a fundamentalist church than any left organization you can think of. The religious have service organizations that do mating as one of their primary charters, we on the left have debating societies, and after the debate ends, you're back on your own.
Activism also becomes a great excuse not to have sex, and usually it's not clear that it accomplishes anything other than sex avoidance.