And what I’m saying is that he did say it doesn’t matter if we use the word evil or not, even if he didn’t use those words.
EDIT: To put it less glibly, the fact that I didn’t need to use the word evil to communicate why the character was evil by @Lanefan ’s definition illustrates the point being made in the OP, which can be summed up as “show, don’t tell.”
But before you can show you have to know what to show!
Let's say I want an actor to act in a certain way and I know the actor is very familiar with D&D.
I give the actor a 3 page list of suggested behaviors. He can show those behaviors, sure.
But if I put just 2 more words at the top of those pages - say Chaotic Evil - I bet he can weave those behaviors together and show them even better. Or if I want it a bit different (again actor is familiar with D&D) and I instead put lawful evil or chaotic neutral. I bet the actor will weave those behaviors together differently. Labels can be useful.