I think it's been this way since the new notes editor was implemented.
- Open a long note that has a vertical scroll bar.
- Click somewhere in the body of the note.
- Neither the vertical scroll bar nor the text scrolls up or down when using the up and down arrows to move the cursor beyond the visible text.
- If you move the cursor beyond the visible text, and then start typing, it does then scroll to the point where you are typing.