NASCAR is strongly looking at hybrid powerplants in the future, GM, HMS, and NASCAR work together on mating a future or existing Cup-spec engine with a potential electric component. If there’s no transparency, GM and HMS have a leg up on the next generation powerplant. Same thing with any tire data they accumulate if Goodyear decides to incorporate it down the road, and same thing with gaining additional track testing for their aero platform.
It’s not dissimilar from what is currently happening in the ramp-up for the next generation of sports car racing prototypes. There’s a new spec hybrid system next year, and Porsche have been testing their car since January. No one else subscribed to the same rule set will roll out until June at earliest. All of the information attained goes to the sanctioning bodies and is disseminated to the other manufacturers. Any tire testing Porsche do for Michelin, the other five manufacturers all get data on. The spec hybrid testing, they all get data on.
All Toyota and Ford want in this case is the same thing. Some might call it crying. Anyone else calls it transparency.