Perhaps the planned obsolescence helped the consumer, because perhaps there would have been no willing producers if producing the lightbulbs at a price the users were willing to pay for wasn't going to turn out to be profitable, with respect to setting up production in the first place and then producing until the investment was paid back.

When we're talking market price, we have to acknowledge that it is a meeting of the price needed to bring a product to market and the price the consumer is willing to pay. We can't assume that the price of the longer lasting bulb would have been attractive to consumers, when compared to the price of the shorter-lived bulb, even if they had all the information available.

It's perfectly valid for a person to decide they'll spend more over the long run, rather than ponying up a larger sum now. And it's perfectly valid for producers to take the chance of deciding this for the consumer. As Henry Ford noted, "If I had asked people what they wanted, they would have said faster horses."

Was anybody stopping anyone from offering the consumer a higher-priced and longer-lasting bulb?