You theoretically could, but then you would have a special weird setup that doesn't match 99.9% of the similar installation base of air conditioners on the same island. Making repairs, maintenance and such very costly. You generally want to generate usable AC power from any significant sort of solar system, so that you can use it for more than just air conditioners.

Yes, but 3-phase AC motors require less maintenance and are more efficient than brushed DC motors. Most traction applications are now using AC motors with inverters instead of DC.