When the upgrade to Android 10 became available, I went to this forum and saw the list of bugs and issues people experienced after the upgrade (in Known bugs & problems with Android 10 ) and decided to wait; there are some serious issues on that list!
Two days ago, I have decided to do the upgrade. Partially because of the constant reminder, and partially thinking that eventually certain apps might not function as well with an older version.
So far, I have experienced no problems, but haven’t noticed any big improvements either (but they can all be ‘under the hood’ type of things).