Conspiracy theories tend to be unfalsifiable claims without counter-explanations, while later-revealed conspiracies have tended to unravel based on credible counter-explanations from the beginning. Yes, the US government imported drugs into inner cities, just as the San Jose Mercury News spelled out, and it's a tragedy that the government then hounded that journalist to suicide before finally admitting it was all true.
In the meantime, hundreds or thousands of claims have been made that have no basis in reality, nothing other than "the world ought to make more sense than it does."
Our planet isn't flat because the US government tested drugs on poor black people without telling them. The latter was consistent with known facts all along, while the former is the result of Dunning-Kruger nonsense.
That oil companies and auto manufacturers are sabotaging Tesla, while competing rocket companies sabotaged SpaceX, is not impossible. It is, however, far less likely than that production is difficult, and that employees treated as Tesla employees are reported to be treated sometimes become disgruntled. So I won't be surprised if there does turn out to be evidence worth charging somebody with, but I think reason suggests that it's less likely than Musk is claiming.
Added to that corporate espionage and disgruntled employees are not opposites. One provides opportunity for the other.