I thought this type of attack had been known and used for a while. Though in the previous styles I’ve seen it’s usually required at least some understanding of the keyboard layout and preparations (hearing each key pressed previously) I don’t know if they’ve jumped that gap, or made some rather huge assumptions. (The victim has the same keyboard as X or the victim has a known keyboard.)
Actually would be interesting to see laptops randomize their keys for passwords, though that would be hellish to type a known password on. I mostly do my password from touch memory.