Smiling Elephant is exactly as good as it needs to be for a city that doesn't have better options. Nashville has better options.
The curries are recognizable and inoffensive. The noodle dishes function. The heat is dialed back. The whole kitchen is calibrated for a market that existed ten years ago, before Nashville's food scene raised its own expectations. In that context, Smiling Elephant would be a reliable neighborhood spot. In this context, it's a restaurant the city has grown past.
The Thai food here would be the best in a smaller city. Nashville isn't a smaller city anymore, and the gap between this and what the city's best Thai kitchens are doing is wide enough to matter.