Cut pork in half crosswise; season all over with salt.
In a medium bowl, combine gochujang, garlic, honey, oil, and ginger. Transfer ¼ cup gochujang mixture to a small bowl and stir in vinegar; set aside for serving. Add pork to bowl with remaining sauce and toss to coat.
Lightly coat an air-fryer basket with cooking spray. Place pork in basket and cook at 350°, turning occasionally, until pork is golden brown and an instant-read thermometer inserted into thickest part registers 140°, 16 to 19 minutes. Let rest about 10 minutes before slicing.
Place pork in lettuce leaves, along with cucumber, scallions, and rice. Serve with reserved sauce alongside.
