I think I once saw either Andrew Gelman or Carl Shulman do the "there is an incredibly small chance that you will decide the whole election, expected utility" version of this argument. It could be worth including as a perspective, but would need an accompanying discussion of the division-of-responsibility problem. Imagine the case where it does come down to one vote, with a hundred million people all thinking they individually decided a whole national election… which, if that was actually happening, they should all be willing to spend their whole life savings to do.