If someone invites you over for dinner in the US you’ll often hear “that meal was amazing!” even if it wasn’t. That’s just polite behavior.
My colleague was saying they don’t really do that in France. You’d never say “that meal was awful”, you’d just say nothing more than “thanks for the meal”.
I thought it was a great example.
You aren't saying it's impolite so say anything less, right? I've lived in the US all my life and that's not my expectation...it could be that cultural expectations are not uniform.
Obviously it’s a generalization, but an observation I found interesting.
So in a restaurant I wrote not say anything (and words not come back), if the meal was truly bad I woke say it was not good and probably leave some comments somewhere (I did it only once because it was really bad).