It’s very hard to rewind the clock and know what would have happened, but let’s try.
First, remember that the Model X reveal occurred in Spring 2012, before the Model S even started shipping meaning it was designed in 2010 or 2011. Tesla was on the ropes financially then and at least until mid 2013 when, against even the most optimistic expectations, the Model S took off like a rocket.
Elon being Elon wanted a flashier vehicle to be able to raise money to secure Tesla’s future. NO ONE would have predicated the future of Tesla solely on an expected eventual 20,000 vehicle a year Model S. It is obvious to us now in 2018, or even in 2016 when the Model X started shipping, that a Rivian-like vehicle would have sold well. But in 2011? A year before the Model S started dribbling off the production line? We remember the 400,000 Model 3 pre-orders, but that was for a $35K car. The Model S reservations were just OK and indeed, collapsed in early 2013.
I think Elon was simply hedging his bets. The Model S was very much a normal car. Would an $80k normal EV sell? No one knew. The X was the ace in the hole in case a normal $80k EV wouldn’t sell. It was the wow car with super car wing doors that would entice people to spend $80k on an EV, just in case the Model S didn’t capture people’s imaginations.
The X did have another effect which was raw PR value. I personally kinda knew about Tesla’s roadster but didn’t pay attention to them too much. the X caught my eye, and once I got a test drive in a friend’s Signature S, it sealed the deal for me for an S.
Ironically, the S was the car that made Tesla and the X was the one that almost broke it again (it turned out the wings were hard to make!), but that was hard to predict in 2011.
But yes, in 20/20 hindsight, a normal SUV would have been better.