I really can't stand Elon Musk, I mean, awesome guy, for sure, I'd love for him to be my boss. But 9/10 times he's doing an interview and he's just rehashing the same story. He has a way of telling the 'reason from first principles' story and jamming it into the interview despite nobody asking any question for which this answer would be relevant, I've heard it a dozen times now.
So no, for me it's definitely not Musk. Cool guy, but you can only hear Martin Luther King have a speech so many times before you're like 'I agree, but I'm getting sleepy.'
For me it's really just the tech and disruption. The things Tesla and SpaceX and SolarCity are doing really are very cool, and they sit at the heart of some of the biggest problems and challenges of the 21st century. An inevitable shift to green energy and the final frontier. For Tesla it's just a cool startup with a slick product, some ballsy moves, frequent run-ins with local/state competition and media clickbait journalists, and a product that for me is a bit like the iphone: not the very first smartphone, touchscreen, mobile os, app store, not the thing the average western consumer will have let alone the average person on the planet, not the cheapest or the most inclusive, but a frontrunner with a huge and lasting impact that will drive everyone else, a company that sets a bar. That's exciting.
And for SpaceX, well, that's just really exciting. This notion we're regularly shipping all kinds of stuff to a freaking permanent space station and returning safely and making multiple trips with the same vehicle over and over, is insane. A one-time planned crash on the moon and on the earth is one thing, but we seem to start to really grasp real control in space, where we can comfortably do lots of different things at an accelerated pace, cheaper and cheaper, and renew the interest, investments and plans in space that laid dormant for a few decades. SpaceX being a part of that, as a private startup company that again is making ballsy moves, is a hugely compelling story.
SolarCity is the least exciting for me personally, but I think it's also hugely important. Generally sits in the top 3 solar companies in the US, doing cool work, like building the biggest ever US solar farm. Creating a solar security, solar leasing options and retrofits (a not so sexy but very important part of our energy discussion). I don't follow the company too much, oil prices have been low recently and shale gas has exploded on the scene, so I expect it to be the most difficult company to run as it's hard to get it cheaper than coal/gas. As solar only has a 'moral' benefit to consumers, and the average customer isn't willing to pay a large premium for something that's moral (because green) especially with all the rhetoric on climate denial, the company is in many ways limited to the growth in the industry. While Tesla and SpaceX can outpace competition, SolarCity probably can't very much.