...I personally never meant to indicate that [he's done nothing on his own], but I do also doubt that he is the primary inventor or designer of most things at Tesla. The "Elon designs everything, is a great person that is just trying his best, and may just be the next Einstein" sounds a bit cult-like.
I see people saying he's a genius. I cannot say otherwise, but mostly I think he's very
important in fostering development of technologies that would otherwise be progressing much more slowly or almost not at all (ironically to this community, self-driving may prove to be the worst example of that statement - depends whether Tesla beats everyone to general affordable L4, or if Tesla gets there somewhat concurrently or even falls behind on failed technical bets). The genius characterization can be taken several ways but I already addressed the use of the Einstein comparison as understandable but maybe not apt.
I certainly don't have the impression that Elon himself, though he is quite technically-minded, has ever claimed that he designs all the FSD stuff himself. In the well-known Autonomy Day presentation He enthusiastically put Andrej Karpathy for ML explanation, Pete Bannon for the silicon design etc., praised their expertise glowingly, and never intimated that he Elon really made the key design decisions.
If people say that Alexander the Great conquered most of the known world, that Solomon built the great Temple, that Edison invented the modern light bulb, those statements are not meant to imply solitary personal action. These were accomplished be armies, civilizations and technical teams. But the immortalized leaders deserve their fame and credit (or blame) for inspiring and directing events.
Elon has clearly accomplished much, and in some areas made the world a better place. He's made it worse in some areas too, in ways that he could have easily avoided.
Ask yourself- if Elon dies tomorrow, will Tesla stock go to 25% of the current value? If not, then maybe he isn't really the singular force some people make him out to be.
Actually I'd guess it would have a shock short-term effect but one would be a fool to put a number on it. Tesla might go on without Elon Musk like Apple goes on without Steve Jobs, but that is actually a credit to their influence rather than a demonstration of their irrelevance.
I can say that if Elon hadn't come along, it's
vastly more likely that Tesla (had it even survived) would have continued to be somewhat of an automotive curiosity rather than a burgeoning, pioneering worldwide giant in cars, solar energy and potentially HVAC. Outside of Tesla, the already stunning importance of SpaceX and very possibly a yet-to-be realized major contribution of Boring are all attributable to Elon's direction. Elon has already been a singular force in all these, despite that he doesn't architect, design and manufacture the products with his own two hands. I see no evidence that he ever narcissistically claimed such fantasies; it would be laughable.