I am pro-capitalism, but I would say that capitalism currently both helps and harms incels. It gives incels a chance to accumulate wealth and therefore at the very least become beta-buxx to a woman, but capitalism is also the same system that allows mediocre women to make $1M on OnlyFans in a day while providing nothing of value besides maybe shaking their ass at a camera.
I'd say that women's rights is the larger problem - increased female choice means more incels who aren't chosen.
Capitalism could also be the system that allows sex to be treated as a service though, too. I'd totally be okay if sex work was de-stigmatized, and in some parts of the world decriminalized, so that incels could safely get at least some form of intimacy.