Good idea. And this is exactly the way I've been using Notes since ages.
I don't care a flying thing about formatting, pictures, HTML or links in the Notes. I just use them for simple plain text to take down a note. All the problems with the Notes Editor have never bothered me. So it's gets my vote. It would be even fine by me if the current Notes editor was ditched altogether and this was implemented. Would save resources. Incidentally, this replacement you describe is about what we had with PB3 which had a simple RTF editor that stored the notes in a RTF file in the thoughts folder. So actually you propose a change to roll back One thing would be needed though. A conversion tool to convert all or a selection of thought notes to the plain text format. And perhaps v.v.
PB user since 1998
Mind over matter? I don't mind and it doesn't matter. TB 22.214.171.124 Pro on Win10.1 Pro 64bit JVM 1.8.0-112