"The dilemma is that they wont't make XD maximally useful as a standalone tool because it then eats into their other offerings like Illustrator or Photoshop."
I can certainly believe this. For a long time, Illustrator only had the option to create a single artboard (page). I'm convinced it was partly due to the overlap with InDesign. If you wanted to create a short document or leaflet, Illustrator would be fine for the purpose - but obviously not if you could only export a single page. Users were clamouring for multiple pages/artboards and Adobe finally introduced the feature in Illustrator CS4 in 2008. (There were over 12 versions of Illustrator prior to this.)
I can certainly believe this. For a long time, Illustrator only had the option to create a single artboard (page). I'm convinced it was partly due to the overlap with InDesign. If you wanted to create a short document or leaflet, Illustrator would be fine for the purpose - but obviously not if you could only export a single page. Users were clamouring for multiple pages/artboards and Adobe finally introduced the feature in Illustrator CS4 in 2008. (There were over 12 versions of Illustrator prior to this.)