Great news, thank you.
For me, the following functionality of OneNote 2016 is missing of the UWP app:
- Install and use offline.
- Save notebooks on computer.
- Export notebooks/sections/pages.
One of my main reasons for choosing OneNote desktop was that it could be used offline completely. Even though we live in a technologically advanced era, several workplaces and situations exists where only offline use is possible. Also, OneNote is not a toy or casual tool (although you don't need to be an expert to learn and use it). It is considered a serious productivity app on which several companies and educational institutes rely every day. In that sense it is similar to other Office applications, like Word, Excel and PowerPoint. I think it is part of any serious software that they could be used in the way the users/companies desire. Supporting and further developing OneNote desktop supports this and strengthens the software. Focusing only on the cloud and on UWP did the opposite.