If you're measuring a human in front a screen with their finger on a button, and the human is young, healthy, and fully alert, then you get 0.2s. Some electronic safety systems[0] can indeed physically respond in µs. Some robotics might have lag due to mechanical slack or software/processing limitations, but that can always be improved.

Whereas humans are never going to do better than 0.2s and will usually do much worse, especially if they have to turn their head, focus their eyes, and manipulate physical controls.

[0]for example: https://youtu.be/ynEdke5dzIU?t=10

(Sub-elite) sprinters average a response time of 119ms

https://www.basvanhooren.com/is-it-possible-to-react-faster-...