>If the US wanted voting to be more popular, there would be a Federal Holiday to promote it.

I agree but it doesn't actually matter. 97% can vote by mail, early, or another method besides election day according to this article https://www.cbsnews.com/news/map-early-voting-mail-ballot-st...

>There is no incentive when there are known costs... is the result of the tyranny of indifference.

What is the cause of the Indifference in your opinion ?

Who said people are indifferent?

They can still actively engage in civil life with a variety of actions that look more relevant and meaningful to them.

If people are not given opportunity to actively engage in meaningful way like contributing to the creation of the laws they will have to follow, then sure they sooner than later they won't bother signing the blank check of void promises.