In a large bowl, whisk together flour, garlic powder, smoked paprika, and salt. Pour in the milk and whisk until smooth - the batter should be thick enough to coat the back of a spoon but still pourable. Add a splash more milk if needed.

Add cauliflower florets to the batter and toss until evenly coated. Let excess batter drip off each piece - too much batter will make them soggy instead of crispy.

Preheat air fryer to 375°F. Arrange cauliflower in a single layer with space between pieces; work in batches if needed. Lightly spray with olive oil. Air fry for 12-14 minutes, shaking the basket halfway through, until deeply golden and crisp at the edges.

While cauliflower cooks, melt butter in a small saucepan over medium-low heat. Remove from heat and whisk in hot sauce and honey until glossy. Keep warm.

Transfer hot cauliflower to a clean bowl, pour buffalo sauce over top, and toss until every piece is coated. The heat from the cauliflower helps the sauce cling. Serve immediately with blue cheese dressing and celery sticks.