In the U.S., I remember a game at Anfield where the NBC commentators literally said “Let’s all take a moment to soak in the atmosphere as the Kop sings ‘YNWA’ and we experience Anfield in full voice!”
It was a fucking embarrassment, as it was clear the volume was turned waaay up to deliver the “famous Kop atmosphere.”
That said, the whole “European night” nonsense feels like it’s a real thing at times. For me, I’ve never experienced the Etihad rocking more than the 2-1 victory over them at our place, when Sané scored the winner, they lost for the only time that season, and we beat them to the title! THAT atmosphere was goosebump-inducing, which I’ve only experienced a few times outside of the QPR & Villa last games of the season Title-winning games.
Like many stereotypes, there’s at least a hint of truth to their atmosphere, but I don’t think it’s anything special in many games.