The context is that certain populations in the US are known to be disenfranchised from getting ID. Here's an example from the Washington Post in 2016: https://www.washingtonpost.com/politics/courts_law/getting-a...
I actually really like the process that Elections Canada uses. They verified that most Canadians have ID (86% have Driver's Licenses). They identified the most common issue (proof of address) and added a mitigating process (mailing Voter Information Cards). And finally, they have a fallback: as a third option, a person's identity can be vouched for by a person who does have ID. https://www.elections.ca/content.aspx?section=med&dir=c76/id... https://www.elections.ca/content.aspx?section=res&dir=poli/r...