Frankly what you're describing is just a new competitor. And while yeah, they'd probably prefer Tesla to not exist, those have always existed. 15 years ago it was the Koreans, before that the Japanese, currently/soon it will be whatever Chinese manufacturer makes it outside the country.

Let's say Tesla does absurdly well and in 10 years, sells 5m cars a year. Not pleasent for the incumbents. But the car market grew by a lot more than just 5m in the past 10. Someone taking a small piece of an increasing pie is not an existential threat.

If Ford were to resort to some nefarious tactics to hurt a competitor, why the hell would they do so for Tesla but not Ford, Toyota or Kia?