I wonder if actually helpful PMS medication would cannibalize e.g. pain medication sales. Generic viagra is super cheap, and in the study they used just one dose. So if that's the actual dosage required in the end, that could cost the pharmaceuticals industry money.

Similar to with vas occlusive contraception. It's really easy, simple, dirt cheap, lasts long, is reversible, non-hormonal, no side effects male contraception. It's basically the perfect contraception and it's the only reversible long-term contraception that men can use.

But it was dropped because it would pretty much annihilate the female contraceptive industry, which makes a huge amount of money each year.

Quote from the Wiki article on RISUG, the form of Vas-occlusive contraception that came closest to getting to market:

Despite this, pharmaceutical companies are reluctant to lose market share of a thriving global market for female contraceptives and condoms which bring billions of dollars of revenue each year. Initially, RISUG attracted some interest from pharmaceutical companies. However, considering that RISUG is an inexpensive, one-time procedure, manufacturers retracted.

https://en.wikipedia.org/wiki/Reversible_inhibition_of_sperm_under_guidance