In a mixing bowl, combine Greek yogurt, lime juice, sriracha, garlic powder, smoked paprika, and salt. Stir until smooth and add water to achieve desired sauce consistency.
In another bowl, toss shrimp with smoked paprika, garlic powder, dried oregano, onion powder, salt, and black pepper until fully coated.
Heat olive oil in a skillet over medium-high heat. Cook shrimp for about 2 minutes per side, until pink and opaque.
Warm tortillas using a skillet or microwave.
Assemble tacos by layering shredded cabbage, cooked shrimp, avocado slices, cilantro, and Cotija cheese on each tortilla.
Drizzle the creamy spicy sauce over the assembled tacos before serving.