So first of all I don’t know shit about anything, but here’s what I’m thinking. There’s an extant misogyny/dislike of femininity in society, such that when AMAB people want to be feminine, society looks down on it, but when an AFAB person wants to be masculine, societies like, yeah that makes sense since men are better. So a subset of AFAB people who might have had gender dysphoria, have it alleviated by being able to be tomboys or butch with less societal pressure than AMAB people who want to do femininity would get. Leading to less potential trans men realizing they are trans. But also the “nature” part of the nature/nurture composite could account for it as you’ve said.
Obviously I can’t say anything for sure as this is speculation, but I have heard at least one trans woman say that part of the motivation for facial feminization surgery was in being able to pass better and being accepted in society as a woman. So perhaps if society was more egalitarian in how men vs women are valued, less demanding that AMAB people fit their assigned gender role, and/or gender roles are abolished then we would see at least some portion of the “why transitioning will help” equation be reduced. Though I think there’s reason to believe even if gender is abolished and there’s no social pressure one way or the other at all we would still find AMAB people who are significantly more comfortable in a female presenting body and vice versa and in the middle too (and I’m lumping together any combination of hormones + top surgery + bottom surgery here, in whatever form they may take in the future). So a spectrum as you said.