I feel people said the same thing about him for SpaceX and Tesla back when he was just the wacky PayPal guy. Remember SpaceX's first launch was in 2006 (before the iPhone existed!) and it's only started getting really serious traction in the past 5 years. Elon's no stranger to things that don't have any "useful form" for well over a decade. I'm quite certain he's aware of the realistic timelines, and he sells a different story in the press for the sake of fundraising and PR.
I think he's really got figured it out tbh - as long as he expects the technology to exist at some point, the fact that he's parked a big chunk of cash in the idea gives him an advantage. It's like he's reserved a spot for his company to exist when the tech exists. His team doesn't necessarily have to be the one actually making breakthrough innovations in order to be in a good position to reap the advantages of said innovations.
I think he's really got figured it out tbh - as long as he expects the technology to exist at some point, the fact that he's parked a big chunk of cash in the idea gives him an advantage. It's like he's reserved a spot for his company to exist when the tech exists. His team doesn't necessarily have to be the one actually making breakthrough innovations in order to be in a good position to reap the advantages of said innovations.