The local election supervisors see no money to be made by advising the prior election supervisor that a person is now registered in their locality.
In today’s high tech age it would be a no-brainer to remove a person’s name from a registration roll when they register elsewhere.
Until the voters make this an issue with their political leaders of both parties nothing will happen.
Maybe it takes a Constitutional Amendment that requires voter identification, voter registration rolls to remove names of people who have registered elsewhere, and non citizens and dead people removed permanently.
In most states, the Secretary of State is responsible for keeping the voter rolls current. It is their responsibility to take dead voters off the register.