Some states do it this way. Other states do it all electronically (fewer now than in the past, thankfully). Other states do it all on paper and do the counting with offline counting machines, then spot check some precincts at random. Some do it by mail entirely on paper.

And that's the big reason why this line of inquiry is nonsense. The entire country showed a huge shift to the right, not just the swing states or the states that are more vulnerable. That's 51 entirely separate election systems that you'd have to manipulate, make sure public information about the election matches exactly, and also not go so far that any independent exit polls show anything fishy either. The scale of conspiracy to do it in even one state, make no mistakes, and have no one leak is hard to believe. Doing it across the entire country? You're going to need a lot more than "I feel like the numbers are fishy" to be convincing. The conservatives were wrong when they said 2020 was rigged, and anyone saying 2024 was rigged is equally wrong.