EDIT: The following is not not incorrect.
They mean the same thing.
> No “real programmers” write code in Assembly.
Scare quotes for sarcasm/inflection.
Would be better and more idiomatic as a singular noun.
> No, “real programmers” write code in Assembly.
The pause here just marks an interjection/response to something else. But it means the same thing (scare quotes and all).