Nah, you weren’t wrong. “Utensils” was fine. “Cutlery” was less fine, because, as mentioned, it is primarily used to refer to knives.
In actual waiterspeak, the usual term is “setups.” As in: “Hey [new busboy whose name I haven’t learned yet], Table 3 needs some setups.”
seconded
It’s regional. If you’ve lived in a few different areas, you will have heard all the variants. As hinted above, “silverware” is the main word for fork/knife/spoon in some areas, regardless of the material the items are made of. (“I bought some plastic silverware for the picnic.”) Mercy be on the prescriptivists of the world as their heads all 'splode in unison with that one.
If you just google “cutlery definition” you get.
So in the US it seems that knives a meaning but in the world at large it is the things we use to eat food in Western countries.
I would typically use cooking utensils and eating utensils
Conversation isn’t English class. What matters in conversation is getting the point across, not being pedantic. Correcting people’s use of language in conversation is strictly reserved for a-holes.
My standard response is, “I’m sorry your mother didn’t care enough about you to teach you manners, but that’s not my problem. You’re being rude and you need to stop it.”