The type of in-person voter fraud that can be identified by an ID is very low, and trying to change an election this way would be very expensive. More people have gone to trial because while they were legally entitled to vote they were unable to get appropriate ID.
Other types of voting fraud, like registering in and voting in multiple districts, is much more common.
The people who for decades fought against requiring ID for so many things said it was a slippery slope. Now you are on the slope, thinking it flat.