Except Boeing and the rest of them are now down to only government contracts. Most commercial launches are now done overseas.
An engineering company would not be gearing up for volume production of their primary product. They would be shopping around trying to sell their design after having proven it.
And your point is? Elon Musk has never been shy about the help they got from NASA and all the pioneers that went before. Since SpaceX is selling launches they are now more than "just" an engineering company. If all they were doing was NASA related activities I'd agree with you; but that is not all they are doing.
If you are looking for big dreams Mr. Musk's stated goal is to retire on Mars. You can't get much bigger than that.
SpaceX has over 40 booked launches for the Falcon 9 and Falcon Heavy, that qualifies for commercial in my books. It's one of the reasons they are looking for an additional launch site.
They also offered to make their mailer similar to Netflix's if the USPS would guarantee the same treatment. The USPS refused.