It’s not that leasing a car is a better deal than financing a car - I agree that financing a car is going to win out financially. However, given the likelihood he moves on from Phoenix in 2-3 years and returns to a city where he does not need a car, I valued the convenience of leasing a car more. I attempted to update the original LH calculation with information for a comparable financing deal, here. Taking a 60 month deal at 5.9% APR (which from my understanding is pretty phenom rate right now), the monthly comparisons between leasing and financing are similar - effective monthly costs of $495 vs. $527. However, the monthly payments as they occur are $409 vs. $554 (in favor of leasing). This is largely due to selling the car after three years of ownership. I used a residual rate of 59% (i.e., the car would sale for $16K which seems reasonable for a base Crosstrek in 3 years).
Regarding your second point, I agree 
. However, there is high likelihood that he moves out of a car-centric environment and back into a city where he won’t need a permanent vehicle.