I think Carmudgeon's point was that it was never designed to do anything for the manufacturers. It was designed to get privateers and amateurs into a class other than the GT class.
Precisely.
There's no question P1 has been the "premier" class in European sportscar racing but P2 used to offer more value to manufacturers and fans than it does now. A few examples of manufacturers, yes engine manufacturers, and fans getting something out of it were Porsche and Honda. When is the last time you went to a race and saw a fan flying a Gibson flag? DPi currently occupies a gray area between P2 and P1 but the point is they have managed to do most of what ACO P2 intends while at the same time offering benefits to manufacturers and fans. IMSA deserves credit for that.
You keep trying to argue a logical fallacy that P2 has anything to do with manufacturers. The sanctioning bodies have been trying to steer manufacturers away from the sub-class and toward the top classes since the demise of LMP675 in 2004.
P2 is a cost-capped, spec class with a spec engine. It is designed to provide a less-costly avenue for privateers and pro-am lineups to compete in prototype-class cars at LM, and in the ELMS and A(sian)LMS. Those are its intended beneficiaries, not manufacturers.
That IMSA has used P2 as a basis for its own top class, with manufacturer involvement, has no bearing on the ACO, WEC, or the other LMS in the rest of the world.
The ACO firmly believes that P1 is its class for manufacturers, with a technology component, to the benefit of both the LM24 and the WEC. Not P2. Even in the face of the troubles caused by VAG's budgetary epiphany and attempt to rehabilitate its image as the result of Dieselgate. Toyota has stood by the ACO and stated that is has no interest in continuing if it was not allowed to promote its hybrid technology, something that would not be affordable for IMSA.
Yet there seems to be a contingent that repeatedly ignores that and believes the ACO should disrupt its own class structure and admit DPis to the LM24. The 24 is the ACO's show, and it has been running it for almost a century.
Would it be interesting to see DPis at Le Sarthe? Certainly. Would it make sense for sports car racing to harmonize the regulations to allow commonality for all the series? No doubt.
But the ACO. while far from perfect, is no more liable to allow IMSA to dictate how it runs its own race than the Hulman-Georges would be to allow the FIA to dictate how the Indy 500 is run.
IMSA is riding a wave now, because GM, HPD, and MNAO see the value in a North American series with relatively affordable budgets and a promising ROI. There are absolutely no guarantees that would translate internationally.
GM, in the face of increased competition in the WT series, has shut down its PWC program. It clearly has budgetary constraints. Where would the budget for a LM assault with a DPi come from? The Vette GTE budget?
HPD is an Honda's NA racing operation. The parent company has its hands full with its F1 grenades. Penske, being a smart businessman, doesn't pay to race out of his own pocket. Who pays for that theoretical program? And Penske, as unimpeachable as its record is, has largely achieved that in the U.S., not internationally. An overall LM24 win is a bucket list item for him, but he has clearly expressed his disdain for flyaway races that do not benefit his sponsors.
Mazda is a small company, that, to its credit, invests a lot in racing. But can it afford to do more? Getting Joest to run its program was a win, and it did spend the money to try to salvage the Riley, but what would it cost to do it properly, to Audi standards, if it wanted to go back for another shot at LM?
The bottom line is that IMSA is IMSA, and the ACO is the ACO. They share a lot, but are also very different, and not the same thing, nor can the same set of criteria be applied to both.