Aha, turns out a lot of people have asked the same thing… for anyone interested, here’s the response:
“I’ve asked someone who used to intern in the admissions office. She said that whether you elaborate or not makes no difference to your application but some admins may feel irritated that you don’t know how to follow instructions if you don’t simply list. Therefore, I’d advise you guys to do what I do (heh) and just write down the book titles and authors. It gives you space to write more books!”
Totally agree. Do not try to read the tea leaves with this, or any other prompt. If the prompt say “list,” then list. If, in this example, Columbia wanted to know your rationale, the prompt would have reflected such.