Your OneNote

OneNotePM , BenSchorr 
I do not know why so many people like the solution, of integrate 2016 in Office 365. Perhaps most do not think what will happen in 2023. We will get the same problem. People continue using old OneNote, OneNote branches will differ more and more. I don't see a nice and long term solution here.

The solution should be, bringing all features of 2016 and 2019 (OneNote for Windows) into one OneNote. The "2019" OneNote has also some improvements which old "2016" has not. (Better use on phones and tablet, Pen features)
Also it's a very frustrating situations, working with a team and some use 2016 and some 2019 (or discuss with them what to use). The solution must be, that there is ONE OneNote of course!!!

I also can't believe that MS want to maintain both OneNote Versions.

And It also will still making people curios when seeing 2 Versions of OneNote available for install. What is the OneNote to use now and in long term?!

But I agree, new 2019 OneNote is really missing a lot features of 2019. That's totally right. I will never understand the step of MS to "replace" OneNote instead of extend it with a such limited feature version as 2019 is. Or course many people complain about that. Nothing to wonder about that.

But, of course 2019 with it's Online editing features is also nice (Nice Online edits, nice integrated in Sharepoint and Teams, better on phone/tablet).

I really hope to see simply a feature rich OneNote 2019 with feature OneNote 2016 has (also with having still the possibility to use OneNote Offline or as shared network solution like 2016 can do)!

And als with integrated all the nice top suggestions for OneNote on the user-voting. All top ideas are really great! 
https://onenote.uservoice.com/forums/327186-onenote-for-windows/filters/top

That's a real solution we need.