I agree, I ran into this same issue on 5/3 (
Delete Notes on Help Desk Ticket). Ended up deleting the contents, leaving the shell of the note. Definitely not ideal. It makes sense if there is a concern on losing history, but a soft delete as jwood mentions seems like a good idea. Just sort of hiding it from view, perhaps then having a link at the bottom showing "Hidden notes..." that when clicked would expand to show the full notes that were hidden, by whom and when.
Effectively getting them out of the way, but allowing review at a later time if necessary.