In the end, the main benefit of Model X comes down to the "no weirdmobiles" company creating the ultimate weirdmobile of them all - and the public relations halo that comes with it. I agree, that effect certainly is real. Model X will definitely go down in history, but if it goes down as a failure, it will be more the DeLorean kind of failure than a Pontiac Aztek.
I'm not saying the falcon wings didn't attempt to address some real issues as well. In the Model X it just pretty much failed to do so (third row access not improved nearly as much as prototype, no folding flat 7-seating due to wings requiring in-seat seatbelts, no real roof-rack solution, probably too limited sensors, not to mention quality issues still).
Child seat access is perhaps the only one they got right, because even access in tight spaces is often offset by trouble accessing the seats in low-ceiling areas. Some of these could be rectified, but would it be worth it...
Wow. Inevitably a failure, huh? That's quite a spin on a car that's already one of the best selling EVs in the country, despite having the highest price tag.
Somehow Tesla managed to make a car that's 30% heavier than my Volt, bigger by more than 10% in every direction, with twice the power and the ability to tow as much as it weighs - an EV first, you'll note - and yet it gets the same EPA ratings my Volt got! Bigger, much faster, more capable, much more comfortable, much safer, and just as efficient? Yeah, that's clearly a total failure.
Have you stopped to think about how long those conventional rear doors you're insisting would be so much better end up? You're in R class or Pacifica territory here - huge doors that you can't open very wide unless you have a huge parking space, like many convertibles have.
I for one am very happy with the set of compromises Tesla chose, and for me an X is a much better car than an S, despite not having children or even regular rear seat passengers. I'm pretty sure I'm not alone.