I'm looking to confirm a few things in case I'm missing any features, options, etc. These questions all apply to the OneNote for Windows 10 App only.
1. Other users of a shared notebook can see custom tags I have used to tag content but they cannot apply those same tags. They must recreate the tags in their own App version.
2. The only way to untag content is to place the cursor to the left of the content and use the backspace key. If the content has more than one tag applied and you only want to remove one, you must remove all the tags and then re-add the others.
3. You cannot create Outlook tasks based on tagged content as you can in OneNote 2016.
4. There is no option to create highlighting for custom tags.
5. In the search results, there is no way to only show only To Do tags that are still unchecked (as you can using Find Tags in OneNote 2016.)
If any of these understandings are wrong, please correct me. Thanks!
All those limitations are definitely why I prefer the desktop application. Those are all correct though I will add that for #2 you can untag something by putting your cursor on the line, then selecting the same tag twice from the ribbon so it is completed then removed. This is likely more clicks though than deleting all and adding.