And I think your categorisation of his work as a tech demo is unfair, and uninformed. SpaceX have built rockets that are delivering satellites into orbit and supplies to the international space station, and have achieved reusability. They have played a significant part in building a private sector space industry. These are not tech demos, they are real things. Can you boast any such achievement in your own life?
Likewise, Tesla have built and sold electric cars that people want. They've created a global re-charging network to supply them. And they've been the first company to deploy significant automation into the automobile market on a large scale. These are not tech demos, any more than the gigafactory rising out o the Nevada desert is.