The whole conspiracy argument is irrelevant. That vehicle used solid rubber tires and was run where and when? What would it do in winter with 10 below temps?

There are no plots by the auto makers or oil companies A 700 mpg car would draw a lot of sales and the oil companies? They would be richer than ever since more people would be driving more often and the roads would need more repairs than ever. It takes oil to make roads and newer roads that are now missing would be demanded by a more dense population of drivers looking for more convenient short cuts.