Have the rules changed so that American drivers with a passport and valid US driver's license really need to also have an "International Driving License"?

I've rented cars and driven them there sevveral times in the past and never had that extra license except once. And no one, including the police at security stop, asked for it. When I pulled it out, the cop laughed and gave it right back.

As you are aware, it’s just a translation of your USA license. If you were going to any other European country, I would tell you it’s a waste of money. However the French most of which speak English, but prefer to act like they have never heard one word of English, I would get it.

Not that I'm aware of. I've had no problems in multiple EU countries and they're all generally the same onregs. The only folks who need to see a license are the rental car companies so if you're concerned I'd touch base with whomever you're renting from.

Try crossing into the eastern part of the EU without one... You like Hungarian or Croatian gaols, no?