Wouldn't this sort of be a prisoner's dilemma sort of situation? The cartel hinges on every producer being complicit, if they are they get all long term small advantage, if they aren't, they and they alone get a huge short term advantage to the detriment of everyone else.

If a single one of them doesn't play ball and start selling "forever lamps" that last a hundred years (slap some patents on running LEDs at their rating, why not), they'll effectively salt the earth for the entire market.