Isn't the point of contextual behavior to consider things like that? So it would act differently in comments.

Absolutely, simple examples would be automatically wrapping comments to 80 characters, adding the comment sigil on the next line when you press enter, enabling spell checking, turning on syntax highlighting if it detects a docstring, changing the semantics for what qualifies as a word, statement, paragraph/block.

So my editor starts applying different keyboard shortcuts as I scroll through the same file?

Yeah, I want distinctly none of that.

And that's the exact reason there are so many text editors to choose from ;)

The same shortcut 'move on a bit more than right arrow'