Renaming is one of the most basic functions in any OS. So why don’t they put it in every program that creates and edits files?
Some will argue that ‘Save as…‘ is there for you to be able to rename a file and save a copy of it. But that means that user has to take extra steps finding and deleting the original file.
It’s hard to believe such basic a function is systematically neglected by software designers… If you know a reason why they do so, please share.