I think you’re dismissing their point too readily. It’s true that there’s nothing I share with every other afab person on the planet other than a box that got ticked by looking at our genitals when we were born, but if I’m looking for someone who shares a particular gendered experience, my best bet is probably another transmasculine person, particularly one who transitioned at a similar age. It’s reductionist and transphobic to argue that one’s socialisation is determined by gender assigned at birth, but it’s also reductionist to pretend it’s irrelevant.
Please don’t. If there’s some of particular interest, link to it with some commentary.