So... the supply side matters but the demand side does not? Pfft.
If you make a thing that has an established fan base, and the fans are not happy, you screwed up. This isn't a problem with fans, it's a you problem. So how do you NOT screw up? You listen to the fans. Ideally, you hire people who are fans themselves.
Let's analogize: say carrots are in high demand - people can't get enough of them. And you tell everyone you have a big shipment of carrots coming in. And you set up a store called "Jim-Bob's Carrot Emporium", and people are lined up around the block... but it turns out the only thing you sell are potatoes... yeah, people are going to be pissed, and they will be justified, because you sold them a lie.