As for the existing ICE car makers.....I'm thinking they will want to limit and ration the growth of EVs. They have too much invested in every aspect of internal combustion to lead the charge away from it. Tesla is forcing their hand....but the whispering campaign currently attempting to undermine confidence in Tesla feels very much like a cheaper way to beat the competition....and it's not by building a better car.
Always going to have those "theories" that both big oil and car manufacturers are trying to limit the growth of anything alternative because it will cost them money
There are also the theories that the issues surrounding the alternatives have already been solved, but in order to make more money things are drip feed to the general population
There is ample evidence to suggest these are theories in the same way that gravity is a theory.