I really want this feature too. I know on android the default is to lock the note but on the PC I've sometimes edited and deleted things which is very annoying if you're not paying attention.
If they simply add another setting to notes to be either locked (read only) or unlocked. (You could have the option to default to either option in preferences. But also then just have a little icon on the toolbar with a padlock or something intuitive. It would take next to no extra data to store that feature and make things so much better.
I've considered using an online wiki instead because you can open the notes in read only mode or editing mode. And when I just want to look up my notes without editing them accidentally that would be really important as a feature to me.