Yet history shows that the greatest "techies" (Kepler, Newton, Galileo, and others) did not work alone and were certainly depending on others to establish their theories and measurements - and many were very much "humanists" and universal thinkers who cared very little about politics and frontiers. Even Einstein who was a key player in developing nuclear power was against any use of it in military conflict. So, I would like to see your list of brilliant and yet cruel techies.
I believe Newton and Galileo worked alone for much of their lives. Kepler was far more intellectually generous.
Newton was certainly known to be a recluse, but he was a teacher in university and spread knowledge around him. Besides, all his work rested on centuries of work before him and he recognized the heritage of others in his discoveries.