> There are other women who have downsized they know majority of male population don't like muscular women it doesn't sell.
It sells to a much smaller market, but there's more than enough men who get hard looking at muscular women, many of whom would never admit it to anybody else.
More importantly, if they want to do generic porn they're up against an almost infinite number of other women.
Whereas muscular women are still unique enough that any who want to get into the sex industry will get noticed and acquire a fan following.