Looks cool from a distance, and looks more user friendly than most! However any modern editor which doesn't support multiple cursors (be it terminal or gui) is missing the start line of the race these days.
Can you even display multiple cursors in terminal?
Sure you can, but you have to use a trick. You can fake it by modifying the background color of the cell where the cursor is located. Many terminal editors have support for multiple cursors.
I assume this doesn’t work if your terminal uses a vertical line to show the cursor?
Yeah that's a drawback -- multi-cursors will be displayed as blocks regardless. As far as I know there is no way to solve that, but using block cursors for multi-cursor operations isn't that bad.
You can emulate it visually with white-background text.