every car had to have the wings a certain way, so all the cars would create vortices.
if everyone could make wings exactly how they like, with no regs, then they could create a wing without "corners" to stop vortices occuring,
then you could judge and say that 1 car is less efficient than another, by looking at which wings produced them.
but the regs say that wings have to be made to a set specification, so either they will all have them, or they all won't have them, or will have them to varying degrees.
RIP Jules, never to be forgotten. #KeepFightingMichael