However, last week, I interviewed and was offered a new job in a EU nation. If I accept their offer, I will
end up making way less money, probably less than USD$89000 per year, before the high taxes in that country.
(but I will live in a EU nation)
When you're deciding whether or not to accept the offer, keep in mind as a US citizen you're going to be taxed on your worldwide income. I.e., you will also pay US tax on income earned in this other EU nation. (And this applies to greencard holders as well.)
If there is a tax treaty, you should get credit for the EU nation taxes that you pay. (Keep in mind though you may get hit with alternative minimum tax (AMT) and may have to pay additional US tax even if you move to a higher tax jurisidiction.) If not, you may want to consult with an international accountant to see what you'd be making net and if you can live with it.