I would venture a guess that on the surface, it's about its verbosity and the pyramids of doom you can get when editing. On a deeper level, I think they might

I would venture a guess that on the surface, it's about its verbosity and the pyramids of doom you can get when editing. On a deeper level, I think they might be frustrated with the ability to develop custom formats (XSDs) which effectively make XML not one format, but a gazillion formats.