There will always be people who don’t vote. Some because they are legally barred from doing so. Some because they are illegally barred from doing so. Some because they are unethically burdened in ways that make it very difficult to do so. Some because they are unethically misinformed in ways that make it difficult to do so.

Then there’s the people who are consistently harmed by both parties like people who self-medicate, people who grew up as descendants of slaves or of destitute indigenous families, criminals who haven’t been barred from voting (those who have are included above).

Only after you get through all these layers can you find the people that choose not to vote because they didn’t care or they didn’t think it would matter or did so out of protest.

And within that group you will find legitimate reasons to protest vote, like genocide.

In short, when we say that only x% of Americans vote, we don’t really mean all those people simply had the option to easily vote and just didn’t want to.