Make the mango salsa: in a bowl combine diced mango, diced shallot, diced jalapeño, chopped cilantro, lime juice, and a pinch of kosher salt and pepper; toss to combine and refrigerate if making ahead.
Cook the coconut rice: in a medium saucepan combine jasmine rice, canned coconut milk, coconut water (or regular water), and 1/4 teaspoon salt; stir and bring to a boil over medium-high heat.
Reduce heat to low, cover, and simmer for about 30 minutes until the liquid is absorbed and the rice is tender.
Fluff the rice with a fork, stir in 1 1/2 tablespoons coconut oil, then fold in the shredded coconut if using; keep warm.
Preheat a grill or grill pan to high heat.
Pat the salmon filets dry and season all over with kosher salt, pepper, garlic powder, smoked paprika, and onion powder.
Grill the salmon skin-side down (if applicable) with the lid closed for 3 to 4 minutes, then gently flip and grill for 2 to 3 minutes more, until the fish is opaque and flakes easily with a fork.
Remove salmon from the grill and serve immediately with coconut rice, topped with the mango salsa.