[quanticle]

    Someone self-studies a pretty challenging book on data structures and
    algorithms and you don't think that makes them curious and motivated to the
    point that you'd not feel comfortable working with them?

Not really, no. There are plenty of grinders who will pick the most difficult book and study it, not because they think it will make them better at solving problems, but because they think it will elevate them above their peers. Why you study is as important as what you study.