People say they want something new and different, but most people get uncomfortable quick and just really want familiarity and nostalgia. This happens everywhere else outside of pinball...
Sports - Why doesn't the NFL change? They make money hand over fist, and when something "new" comes along like the XFL it fails because no one knows the players and it's not something popular enough to discuss with other people.
Music - People: "Why doesn't anyone make ORIGINAL music anymore?!" Indpendent/Soundcloud/Whatever you want to call it hip-hop artists: "Here give this a try" People: "No not like that, I meant why don't people make music that sounds what I've listened to for the past 25 years!"
Food/Beer: "Craft beer? These hipsters and their IPAs! Can't beat my trusty Bud Light". Compare the line at a McDonalds to any of the independent/smaller restaurants on the same block at lunch time.
TVs: Remember 3D TVs? Curved TVs? HD-DVD? All dead products that no one bought.
People fear and hate change. I'm not saying I'm any different ha, but people will always gravitate to what's familiar. P3 is probably the biggest risk pinball has taken in years. I'm not privy to their sales or financials, so I don't know how we'll it's selling or how popular it is, but I'll tell you I've only seen one once in person at a show maybe 2 years ago, and never on location, where as I can find any new JJP/Stern game within minutes of my house on the day of release to play. Familiar sells, innovation is a risk. Wish it was the opposite.