Watching 10 second games. How do they move that fast?

Premoves, yes. But if you look at the game I posted, by move 10 (probably earlier) they are obviously reacting to each other's moves, sometimes in .1 second or less. How is that even physically possible?
that GM dude Brewington Hardaway... i've watched him find combinations for mate in 10 second games. Insanely, madly, impossibly good. i guess when we're watching those top boards, it's important to keep in mind these are super-GMs, like the best 16 players out of 7 billion. Guys like Hardaway are like another species.
10 seconds, .1 increment. They move faster than I can move my eyes.
Are they using a mouse, touchpad, Neuralink, touchscreen, or?
https://www.chess.com/game/live/143819817404?username=pursuitofhappyness2