Do people really believe that Tesla is literally run 10x better than Toyota, Volkswagen, Daimler, BMW or Honda? I don't think so.
Then there's the nightmare of trying to appeal to two wildly different consumer groups.
At the low end: does Tesla have a meaningful reliability advantage versus Honda and Toyota? From what I have seen, it appears not. This matters less when you're dealing with premium buyers, but will not work with the mass market. Fans will put up with hassle (I own an AMG... I'm more than aware of the extra expense I am constantly paying for - and that's a trade-off I'm happy to make in return for a powerful v8).
Secondly from a clout point of view: why would anyone buy a Tesla over a comparatively priced Audi, Porsche, Mercedes or BMW. The people who talk about their Model 3 with a burning passion aren't trading in a 911, or an E Class or a Q7. They're excited to upgrade from a 2015 Camry. Massive expectation gap.
Plus, all of these companies are valued far more realistically. Tesla being worth more than every other automaker or whatever gives them very little room to breathe. If Tesla is ever valued as the hardware manufacturer with relatively low margins (when compared to say a tech stock like Facebook or Salesforce).. is the day that we will see an enormous valuation haircut.