You’re usually autosaving. So it’s not every character, but maybe every minute and lots of other logical triggers like running the file. I’ve found it works very well.
In Emacs, if you select a region of text and invoke undo, it applies only to the selected text. Very useful sometimes.
(But also buggy...)
Seriously. This is one of those features I forget other people don't have access to. Anything less is just uninspired.
VS Code has this feature too, it's just not known.
And with the diff panel you can easily cherry pick selected changes to apply.