I do not understand how anyone can have this line of thinking. They are in clearly different classes. When I wanted small sport sedans I bought M3s. I didn't cross shop 7 series and Cayennes because I didn't want a large car or an SUV.I think he is right on the HUD. There is an important implication. First, Musk can't do the second reveal until he is damn sure the car is ready for production because he will kill S/X sales. If they kill S/X sales, they have to do a fast ramp.
I'm assuming Tesla doesn't have the capacity to get superHUD into the S/X before model 3 release. I assume this is why Musk keeps telling S/X owners how much he appreciates their support.
Tesla may not have planned for UI 2.0 to go into the Model 3 first. It may have been targeted in the model X.
The ghosting in the model X windshield may be a HUD lamination layer, as I suggested in another thread.
When I wanted a large sedan I bought a Model S - I didn't cross-shop a 3 series and I still didn't give the Cayenne a look.
It's not like there is a defined pool of electric car buyers and they just choose among the 4-5 different options. It's not 2010 anymore. The Model 3 is growing the pool of potential buyers, massively. So far, the reveal is bringing in more Model S/X buyers as people are introduced to Tesla for the first time or start to become seriously interested in the idea of an electric car. There's no reason to think this trend will stop. People follow the herd - if 500k can get behind the Model 3, then there must be some staying power to this whole battery car thing.
I concede that at the margins some potential S buyers will buy a 3 instead once both are available. The appeal of the S is so strong that many people who prefer small cars are willing to go against their desire for a small car in order to own the S. My opinion (which is actually happening so far) is that this "cannibalization" figure will be dwarfed by the larger pool of people buying in to the idea of electric cars and buying the S. These are buyers drawn into the Tesla brand by the Model 3 hype and buy an S after testing it out or after deciding they need one NOW. I don't think X cannibalization will occur at all. A small sedan has nothing in common with a large 7 seater SUV.