Having MathML being XML based plays rather nicely with both HTML and SVG. And I am saying that while not being exactly a fan of XML-based formats.

> The initial vision of MathML was that people would write it in a WYSIWYG editor (since it’s far too verbose to write by hand), but that grossly misjudged users’ preferences

To be honest, it probably depends heavily on a particular audience. I know people who barely wraps their heads around the concept of BBCode, and those (although a much smaller group) who would probably advocate for exchanging Microsoft Word for a LaTeX editor. Most people out here are probably completely content with a WYSIWYG editor and don’t care about the inner mechanism of its implementation as long as it gives an expected effect for them.