Mostly hogwash. It's probable that the oil companies have tried to suppress electric vehicles, but the rest really is typical American conspiracy theory stuff.
Investors short Tesla because it's valued almost as much as Ford, but is miniscule in comparison on almost every other measure - including revenues, production capacity, earnings, cash in bank, assets etc, etc. Tesla bleed cash day on day and are on an almost permanent lifeline of regular new cash injection to keep them afloat. All it will take is one of the big guys (VAG, MB, BMW, Ford, GM etc) to come up with competitive cars and Tesla's valuation will be severely hit. All the evidence is that they are ALL very close to launching competitive vehicles.
Don't get me wrong, I like Teslas and think they do have a march on the big boys, but it won't last. They'll get snapped up for their tech at some point and that'll be it.