It's not about voter fraud, which is so vanishingly rare that it doesn't really require this.
It's not about ID cards, which would be pretty unpopular with Tory voters.
It's about voter suppression and alongside some gerrymandering, closing the back door to ensure that something like 2017, when an unexpectedly large number of young people rushed the polling booths and denied the Tories a majority, never happens again.
With many minorities and the young either unable to afford expensive ID, or unwilling to be registered in such a way, it paves the way for our silly little island's blood spitting, spite fuelled boomers and pensioners to vote in endless Tory governments.