Tulum has two very different eating scenes. The beach road is where the much-photographed, candle-lit, jungle-canopy restaurants live: ambitious, expensive, and often genuinely good, drawing chefs from Mexico City, New York, and Europe. The Pueblo is where Tulum eats when it is not posting about it: taquerías, marisquerías, family-run kitchens where two people can eat well for the cost of a single beach cocktail.
Both are worth your time. Mix them. Have a long jungle dinner once, then alternate between pueblo lunch spots and beach club lunches for the rest of your stay.