Good old ballot stuffing or bags of votes being conveniently lost is still a thing though. There's a lot of reasons why you'd still want to use it in conjunction with just putting the thumb on the reporting scale.
That's just altering the results and providing paperwork to justify it. It's not trying to do anything through the legitimate voting process.
The Republican/Trumpist/etc. fear is that Democrats will swarm the ballot box with millions of Mexicans and other illegal immigrants (predominantly Islamic) to vote Marxist, well, not anymore, now it's just that they'll mail in billions more ballots than there are registered voters. It always assumes someone will try to cheat the fairly airtight process, not do anything after the fact to alter the results which are somehow inherently sacrosanct. Someone voting without an ID or whatever "loophole" would lead to the polls being rushed by trillions of these voters is only a problem if they're doing it in another persons name denying that person a chance to cast
their ballot. If they're not and merely adding a few votes to the total who gives a fuck. Especially if they're a resident.