The evolution of HTML and CSS clearly shows that HTML isn't suited to describe a interface without massive hints to a rendering engine to manipulate it
I have no experience with blender but have been developing for maya for 7+ years or so. Python in Maya is very much a afterthought and extremely slow (even for Python standards). There is noting pythonic about the api which by all means is just a port of the mel interface.
The documentation is great, agreed, but I am not sure you can attribute that to the python part of Maya. The documentation structure goes back to pre python days.
If any of the major studios spent a fraction of their development budget on Blender rather than Maya (and contributed back to the community) I think we could see great strides in polishing Blenders usability for scripting.