The dude did not, in fact, build those things. The dude was present for them in some capacity.

And Tesla is hardly a juggernaut, their cars have horrible build quality (speaking as someone who owns a Tesla) and are likely to face stiff competition in the next five years from companies that know how to actually build cars.

Tesla's market share is approximately 14%. They are impressive, innovative and might have a bright future but they aren't at the juggernaut stage yet. Their huge market cap and cultural share is because of their dominance in a small, previously ignored subset of the market that is expected to grow.