Isn't it true that throughout history, people with Swyer syndrome were simply considered to be (infertile) women, and only very recently did we realize "oh crap, they got XY chromosomes, actuli". For all we know, Elizabeth I may have had XY chromosomes.
In any case, I think we can basically decide where we want to draw the boundaries of the "woman" concept, much like we can decide where we want to draw the boundaries of the "German language" concept or something.
For utilitarian reasons, I think that transwomen should be included in the "woman" category, and also poking fun at anti-trans people is, of course, a source of boundless amusement.