I suspect Republicans vote more races than Democrats.
If so, the possibility exists that a stray finger might switch a touchscreen selection from say Trump to Harris and such switches would favor Harris.
They are computers people they can do anything they are programmed to do. The tabulations devices are computers as well and they can be programed. They can also determine exactly how many votes are required and in which districts they need be add to change the outcome. Who controls most of they high tech industry? Hint it isn't republicans or democrats with a conservative bent.