Stop what?

Using accurate information? Not ignoring the complexities of the world?

That comment is absolutely correct; to make things more confusing, people whose sex appears female can turn out to have XY allosomes in some, or all[0], of their cells.

0: https://www.invitra.com/en/morris-syndrome/

As the article you’ve linked states this syndrome affects males, makes them resistant to androgens, so they have an appearance of females.

It doesn’t state anywhere that the patients are either female or belong to a novel category.

From your own link Morris syndrome affects males. In fact, the presence of a Y chromosome by definition means the person is of male sex and it really is as simple as that. One's appearance has no effect on their sex.