In a large bowl, combine the shrimp, olive oil, smoked paprika, cayenne pepper, garlic powder, cumin, salt, and pepper. Toss well to coat the shrimp evenly with the spices.
Heat a large skillet over medium-high heat. Once hot, add the seasoned shrimp and cook for 3-4 minutes, stirring occasionally, until the shrimp are opaque and cooked through.
While the shrimp is cooking, prepare the lime crema by whisking together the sour cream, mayonnaise, lime zest, lime juice, and salt in a small bowl. Adjust seasoning if needed and set aside.
Warm the corn tortillas in a dry skillet for about 30 seconds on each side to make them pliable.
To assemble the tacos, layer some shredded cabbage on each tortilla, followed by a few shrimp and slices of avocado. Drizzle with lime crema and garnish with fresh cilantro.