It's amazing to me the amount of negativity directed toward his projects and the millions of reasons people give for why they "won't work" (not necessarily on HN, but at least on general news websites). I'm starting to believe the only difference between those who start their own companies and those who don't is that the latter convinces themselves that it is impossible, never builds anything, and from their own lack…
Meat-space engineering is hard. I'm an early '90s kid who grew up hearing about how we're going to put people on Mars by 2020.[1] I got a degree in aerospace because of that! Then I realized that physics hates you most of the field is about eking out 1% more fuel economy every decade so United can turn a slight profit. Even Space X is more interesting from a business model point of view than an engineering point of view. It's like someone figured out how to make a $10 iPhone 3g in 2017. Neat, I guess.
[1] Almost everything pop science said would happen was a lie. Moon bases, NYC-London flights, flying cars, etc. Outside of computers and pharma, technology has progressed at a glacial pace over the last 40 years. If you transported someone from 1890 to 1950, planes, international calls, etc. would blow their minds. If you transported someone from 1950 to 2010, I think that they'd frankly be disappointed.