I enjoy the Triggernometry and Benjamin Boyce podcasts but have seen two this week that left me a bit 
Triggernometry had Blaire White on who asserted that trans IDs are caused by in vitro hormone wash.
And BB had someone on with CAIS (Complete androgen insensitivity syndrome), who said [paraphrase] we all start out female and that the inability of those with CAIS to use testosterone means sufferers are female.
As far as I'm aware hormone wash is an unproven theory, not a proven fact. CAIS is a DSD only found in genetic males. And no, we don't all start out female. While there is no visible* sex differentiation initially, sex is determined at conception and is a result of the sperm carrying a Y chromosome (or not).
The comments on both videos were largely gushing when I looked, and it makes me think about how this kind of thing impacts the discussion.
*this is not a value judgement