I'd have to say there is a good use case for textbooks in engineering. Go into any mechanical engineer or chemical engineers cubical and you will find that they all have many of their college textbooks. Textbook chapters are a way better organized than websites when you are looking up values in tables, applying them to equations, and adapting example problems.
That's not anything that couldn't be solved with a better designed informational website or app. Those textbooks persist only because someone's making a lot of money from making them required parts of a course.
