People like David Marcus fancy themselves "intellectuals" while rejecting the very basis of being an intellectual - science. Science today makes it very clear what makes trans people, both transmen and transwomen, tick. It confirms that transwomen are female in their brains and that we don't know how to change that short of killing someone. It confirms that transmen are male in their brains and likewise we cannot change that. But we can change other things about ourselves, yet the act of us making that change so terrifies these "intellectuals" that they rant on and on using baseless superstition and myths to bolster their pseudo-intellectual positions.
It's truly sad because despite the plethora of scientific studies about this, age-old superstitions continue to persist, and continue to get dressed up and doused with an "intellectual house dressing" to make them seem palatable to the pseudo-intellectual right wing, who then pat themselves on the back at their supposed intellectual superiority, all the while rejecting the science that says otherwise.
You see this not just with transphobia, but climate change deniers, and even those people who try to deny the age of the universe and the earth, instead insisting that it really is "scientific" to believe the earth is just 6000 years old.
So the problem is not just transphobia, but an entire mindset that pretends towards intellectualism while at the same time rejecting any real basis for intellectual debate and discussion - science.