Yes, if I notice it I can undo obviously! The problem is when I realize the mistake a few edits later...

It does :)

Undo in emacs isn't on a very intuitive place.

Those people are complaining that they don't want to learn a new complex UI (what it is - I have wondered in the past if it wouldn't be better for me to simply disable org-mode and edit the files as plain text). Getting using to the undo is part of it.