There were plenty of people with the same attitude in the early 20th century who said that we'd never visit the moon another planet. Or that the rockets would pierce the dome of the heavens and the stars would fall to earth (this was not an unpopular theory). I'd rather side with the unrealistic dreamers rather than the apocryphal patent commissioner who stated everything was already invented.
Humanity should always strive for what we do not have, it would still be stuck griming about in the mud if it did not. It's the old conflict between pure/theoretical science and applied science. Sometimes, when researching the 'impossible', you get it. And sometimes you find something entirely unexpected which might be far more practical.