I have no problem believing this. In my little borough of 500 people I know there are dozens of people who no longer live here or are dead that are still on the rolls as well as folks who got married and their names are on the rolls twice.
Not due to anyone being nepharious but because the system is that messed up. I’d be beyond amazed in the number of invalid and illegal registrations are only 100k state wide.
I’d bet its 10x that!!