"Gender" is just a word. Words have meanings, and meanings can change over time. As with gender and sex, you seem to be confusing your stubbornness with common sense.

> The new “right-think” on gender and sex seems to directly contradict basic common sense. You’re born with a set of parts and chopping them off doesn’t change who you are.

But no one thinks chopping of parts changes who you are.

The reactionary view on gender thinks the parts determine who you are and continue to do so after you chop them off, while the nonreactionary view is that the parts don't determine who you so chopping them off doesn't change that.