Even the fastest "real-time" LLM frameworks currently report sub-second latencies around 120ms. This is fine for high-level mission planning (e.g., "fly to the red house") but too slow to prevent a drone from hitting a tree at 50mph (80 KM/h)[1]
Whilst the Shahed-136 kamikaze drone typically flies at a maximum speed of around 185 km/h (roughly 115 mph or 100 knots).
[1] https://arxiv.org/html/2602.19534v1 [2] https://en.wikipedia.org/wiki/HESA_Shahed_136
LLMs (Large Language Models) are far from the only type of AI around. It's a pretty broad field, and there are real-time AI systems, for example, self-driving cars, which have the response times you're thinking of. [1]
[1] https://en.wikipedia.org/wiki/Artificial_Intelligence:_A_Mod...
YOLO is a good example for something that can work.