Thanks for the helpful information.

I’m currently applying for my Irish passport, which will be my third (alongside Canada and the UK). Thanks to Brexit, I’m in need of another EU passport.

Fortunately, none of those three countries has compulsory military service, mandatory voting, or double taxation. Unless I reside in any of the countries, I don’t owe them any tax. As far as I know, the US is unusual in demanding that even overseas citizens file a tax return — though probably not unique.