Is OneNote 2016 similar to the OneNote that was part of Office 2010?

I just upgraded from Windows 7 / Office 2010 to Windows 10 and the version of OneNote I used previously was faster, had many more features, and felt like a desktop app.

This new version feels slow and looks like it was a horrible port from a mobile phone or something. Does OneNote 2016 have more features with a more desktop feel to it?

I'm considering rolling it back or ditching OneNote altogether. This does not feel like an improvement at all!

I have desktop ON2016 and it's great. You obviously have either ON for Win10 or more likely OneNote Web App—see below. Did you also upgrade from Office 2010 to Office 2016 or 365?

Here are the differences:
What's the difference between OneNote and OneNote 2016?
What’s the difference between OneNote and OneNote 2016? [different article]

Microsoft have made a dog's dinner of the current OneNotes—yes, that's plural, there are 3 versions now.
OneNote 2016/365;
OneNote Win10;
OneNote web app.

Read all this thread, good stuff in it:
OneNote 2016 vs. OneNote for Windows 10

I always get the upgrade notice when opening MS OneNote 2010 and always dismiss that. I don't need any extra facilities of any later version, and the look maybe different. This is a Desktop application.

That did not change with Windows 10.
If you look in the All Programs list you will find "Microsoft OneNote 2010" in the Microsoft Office folder.
You can make a Tile, Taskbar icon, Desktop shortcut as before.

You are probably starting up the UWP version which is part of Windows 10. That looks very different.

Yet another version, the online OneNote which looks rather similar to the UWP version.

It is confusing having access to 3 versions.