The company isn't "rapidly developing" anything. That's typical Elon BS, like when he said there would be a million level five autonomous Tesla robo-taxis on the road by the end of 2020. Or when he said the Tesla factory would be like an "alien dreadnought" with machines moving so fast you would need a strobe light to see them. Instead, he builds cars mostly by hand in a tent. He is the ultimate snake-oil salesman. Tesla's R&D spending is a joke. They've been losing engineering and executive talent to their rivals for years. If they had top notch battery tech, they wouldn't need to source them from Panasonic or CATL. Nor would independent testing find that they habitually overstate the battery range in their cars. They are getting taken apart by incumbent manufacturers in battery tech, driver assist and are losing more market share by the day. They've had to slash their asking price per car 13% in the last year to move metal. They are absolutely fundamentally a car company, and an abysmally run one at that.
Their solar division is the neglected stepchild. Elon coerced Tesla's board into buying out SolarCity because it was insolvent. Consultants opined that it was not a going concern, and suggesting lining up DIP financing--they could not drum up interest in a takeover from a single PE shop. Its demise would have destroyed Elon's and his family's stake, as well as $200 million of SpaceX venture cap money that he had parked in SolarCity bonds. Default would've likely brought down SpaceX too. So Elon threw his weight around and claimed how synergistic and game-changing the merger would be, then paid an excessive premium for the moribund company that paid off his cousins handsomely and got him and the board sued by Tesla shareholders. After Tesla acquired it, solar panel installations plunged. Dig through their reports and look at the kilowatt hours installed. They're minute compared to five years ago. Their panels have been plagued by installation problems and fires. Go read reviews from customers. Scathing almost universally. The so-called "game-changing" solar roof, which is immensely difficult to install and often costs six figures, is hardly a viable solution for 99.9% of the populace. There are maybe a hundred in existence, and that is generous.
As for SpaceX, they've done some cool engineering stuff. The Falcon is a reliable workhorse and Elon can't afford to cut corners with it, especially if they are transporting humans. Dead astronauts mean intense government scrutiny, which is the last thing he wants. But let's be clear, as a business, it is still a money loser built on clearly wrong assumptions. How many companies do you know that still need venture capital after 20 years of operation? A company that old should be mature enough to stand on its own, go public and allow VCs to parachute out, but not SpaceX. That alone tells me it is probably hemorrhaging cash like every other project Musk touches. The whole yarn about how reusing the booster would save so much money on launches was BS too. After all the recovery, repairs and inspections are done, it's every bit as expensive as a disposable launch vehicle, even if the landing boosters are cool. In fact, Space X recently was the most expensive per-launch bidder for a recent contract. The whole constellation of internet satellites Elon bloviates about occasionally is just another pretext for raising more money, all the while filling low earth orbit with space junk. They are not launching astronauts to the moon. The NASA SLS booster will be doing the lifting. SpaceX got a contract for the rendezvous once they reach the moon.
I've never heard of a Tesla car fire making the U.S. news. China, yes. But a car with no driver slamming into a tree and killing its occupants is certainly newsworthy, especially when that car company's CEO has been criminally exaggerating the capabilities of its driver assist software for years. You see videos all over the internet of idiots pulling stunts like this; who knows how many others have gotten themselves killed by trusting faulty software and will get other innocent bystanders killed before a regulator steps in and says enough is enough.
These are not companies that are changing the world for the better. These are companies that survive by syphoning billions in taxpayer subsidies, and raising billions more in new capital from gullible investors who can be duped into believing fanciful narratives. Without historically loose money, and no hurdle rate for investment, Tesla and SpaceX would probably have been consigned to the dustbin of business history long ago.