It's like trying to teach evolution to a creationist...
This explains a lot from your standpoint.
Diesel takes at minimum 25% more crude to produce. That alone, but with increased refining cost due to reducing sulfur, the cost of producing diesel is equivalent or more than gasoline.
Please review the current gasoline vs diesel prices in CA showing price are equivalent. So if it cost more to produce and sells for about the same as gas, your argument is full of holes, because there is more profit in producing gasoline than diesel.
Instead of making up stuff, please show us references to back up your argument!