"The first problem we run into when discussing supposed gender ideology is the inability of the people who use it to give a coherent definition."

Bingo. The speaker's grasp of this term is one of the first things I want to know when he uses it, because its meaning in any individual case is opaque. The thing is, I think most people using the term don't have a coherent grasp of it. I think it tends to be used to refer to whatever they don't like about the very concept of gender and/or applications that offend or horrify them.

To be fair, I think there is a great deal of confusion on the trans side, as well, concerning the concept of gender and its significance. It's a real mess.