Society always believed in gender, we all know that. But 'innate gender' or 'brain sex' or 'born in the wrong body' only became the 'standard' trans story relatively recently. Actually, it was a bit of a rehash, given that 'born in the wrong body' used to be an 'explanation' (okay, even I'm getting tired of all the inverted commas here!) for butch lesbians (who should obviously have been men, really, rather than inverts or the damned third sex. As opposed to femme partners who were confused ordinary women, see 'The Well of Loneliness'.....), or for effeminate gay men. Other than the 'weird hormones' explanation, or hormone washes in the womb, or how many elder siblings (did you go measure your finger ratio?).
But now this innate gender/brain sex line is so much the norm that it is twisting what little research has been done in the area. So, for example, those brain region size papers, who of course compare female on this end of the spectrum, male on the other end, and then find that trans is somewhere in the middle (and closer to the sex they identify as rather than their birth sex). Apart from the fact that the stats and the methodology of the papers is nonsense, just the fact that they are projecting their data onto that simple male/female axis and expecting trans to be somewhere in between speaks volumes. They aren't questioning that this is the sort of comparison to be making in this case.
What doesn't seem to be being looked at (or please elucidate if anyone has any info) is where dysphoria comes from, and whether the bodily gender/sex dysphoria is different in essence from other dysphorias. Instead, it seems (amongst lay folk at least), to be the obvious and logical response to a belief that the brain is sexed and being sexed differently to the body. Of course you'd have dysphoria!
Seems to me you can't ask the real questions (what exactly is trans and what helps gender dysphoria) because we are supposed to already know from the accounts of transfolk (apart from the ones like Anne Lawrence who say autogynephilia, but they are obviously not real trans or at least not the right sort of trans!), hence asking the questions is transphobia cos it's disbelieving transfolk...............