I usually wouldnt say this but that's just flatout wrong lmao. Even if you take away the fact that this is a Japanese person speaking to an ancient Greek child and an alien snowman of unknown origin, even if you take away the translation between 料理 and "cooking", the definition of words is still very flexible. "Cooking" can mean both an item but also an action turned into a noun (i am cooking, mama's cooking). They also have subjective meanings to the person, which is why i didnt use the word "cuisine" which 料理 also means. Cuisine in English has an ethnic connotation, we dont refer to everyday foods as "cuisine", we use cuisine to refer to where it comes from (french cuisine, Italian cuisine, hon hon baguette). Saburo's focus is on comfort food and is very atypical for style (like udon noodles for pasta dishes), thus i used "cooking" instead of "cuisine" but comments have already talked about how cuisine is probably more appropriate, since cooking also has connotations of "boring" and "unimpressive".
So if we also include the fact none of these characters have ever heard of the word "delicious" before and that they're only able to communicate with each other due to matrix bending forces that turn language universal (something that's biologically impossible without literal magic), the etymology of this universe is far from set in stone, and discussions of words isnt too crazy to have.