The individual experience is irrelevant for the effectiveness of a medicine or the height of a building.
But of you want to have a own opinion, a (personal) believe or your own conclusion about a thing, then the things you have read and the ideas you have thought, so your experiences, are necessary and the only thing forming your believe/opinion/conclusion.
This can be wrong or changed, if the person recieves more information, like if they think their specific god has spoken to them, then their believe might change. Or they explain the fact in another way and still dont believe.
All of this is personal and not set in stone
A good image to have if a discussion about "men in women sport" breaks out. I heard so often: if XY then Man.
The whole spectrum of intersex is too complicated for the average today joe...
And then comes the even more complex topic of transgender people and gender affirming care/therapy, which can be a totally separate thing besides the intersex-biology-discussion