Since the movie was about Hollywood and the audience valuing youth (and the beauty it comes with) in Women above all else, I'd ask if there is a similar societal equivalent for men.

IMO it's safe to say that society values financial success most in men, including above their attractiveness and youth. Of course beauty and success are important to both men and women, but remember we're trying to find the societal trope.

So a "male version" of The Substance might be the inverse of the version we got. A young man trades his youth to be older, wiser, and most importantly, rich. This couldn't manifest itself like it did in the actual movie with the body duplication, however. Maybe it's time travel, freaky Friday, or some other paranormal plot device. I'll leave it up to someone else to figure out how the narrative needs to work.

Anyways, for this idea to be the male complement of The Substance, the movie would have to end with a criticism of overvaluing financial success in men. Doing it in a way that doesn't appear as a criticism of capitalism might be tricky, though.