It's interesting going between small parts and then bigger roles where you carry the film. If the writing is good, and if the people involved have integrity, then you'll do it, even if it's only five minutes on screen.
History proves abundantly that pure science, undertaken without regard to applications to human needs, is usually ultimately of direct benefit to mankind.
Back in the mid-1970s, we adopted some fairly ambitious goals to improve efficiency of our cars. What did we get? We got a tremendous boost in efficiency.