The Leaf is using a synchronous motor which is actually more efficient but a little more complex than the asynchronous motor (used in the Model S). BMW's i3 is one of the most efficient EVs (look up it's EPA ratings) and is using a permanent magnet motor. BMW has been experimenting with EVs for a long time (Mini-e and Active E).
The Model S is, compared to other EVs, pretty inefficient. Part of it is the weight and size but part is the motor and inverter being designed for performance rather than efficiency. The different motor types have their pros and cons, but all have been around for decades and none of them is inherently better than the other.
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Price might not be a factor for you, but it is a factor for many people. May I remind you of all the Leafs, Spark EVs, RAV4 EVs, Smart E, Golf E, ...? Not everyone buys their car based on the longest trip they might have to take. If the competitor was $30k less than the Model X I can have a private limo service for all my long distance trips for the price difference.
Being able to drive electric isn't worth an arbitrary amount of money. Most people can't afford a Model X. An EV that isn't as capable for long distance trips might still be a very valid option when long distance trips are sparse and can easily be managed with a rental car or other alternatives.