I completely agree. Of course, I'm probably the most provocative of the bunch, and I would say that we need different language. It's not about a GBA, it's not about GBA+. It's about mainstreaming equality, leaving no one behind, and looking at gender in relation to other kinds of factors.
There is resistance to GBA, because it's still thought to be about women. When I've done training in departments and talked about intersectionality, you get a lot more traction for gender when you place it in an intersectional framework. You get a much more nuanced, complex, and realistic understanding of the relational aspects of gender in context with other factors. Look at the social determinants of health, for example. Gender is among many different factors.