His point was that control theory is a mature field and that we field very sophisticated control systems in daily life that may be far beyond what's needed to land a rocket vertically. However, the vast majority of those systems are embedded in industrial machinery that doesn't seem particularly exciting from the outside.
If it helps, bear in mind that John Carmack's Armadillo Aerospace was landing rockets vertically about 17 years ago. And that was a garage operation of about 5 people.
Engineering students build inverted pendulum control systems all the time for fun and for class projects: https://www.youtube.com/watch?v=MWJHcI7UcuE
If it helps, bear in mind that John Carmack's Armadillo Aerospace was landing rockets vertically about 17 years ago. And that was a garage operation of about 5 people.