@jenstornell: yes, of course you can sort, edit and delete a normal list within an textarea field as well. I think the idea here is to have a separate list field which you can sort by dragging and dropping, so as to make handling easier. I don’t know how often you would need such an isolated list, however. Usually, I would put such a list within surrounding text.
As for more complex lists with headlines and paragraphs, which tend to get broken easily using markdown, I would opt for a standard structure field, anyway.