For those who still use OneNote 2016 and still do not have moved to the OneNote Windows 10 app (I am one of them 
) – probably because there is still to much gap between OneNote 2016 and OneNote app, here is a good news.
Despite what was announced in 2018, Microsoft is reversing and is now continuing OneNote 2016 mainstream support, meaning you will continue to get updates for OneNote
Also OneNote 2016 is getting back in default Office installation starting March 10th, 2020.
If you are deploying Office in a managed way with OneNote already set for installation, you have nothing to do.
If you are deploying Office in a managed way with OneNote already excluded, you have nothing to do.
If you are deploying Office in an unmanaged way, OneNote 2016 will then be installed by default (again).
Also https://config.office.com/ (the Office installation configuration tool), SCCM and/or Intune will also have OneNote set for installation by default.