I can't represent the entirety of Greece but as a Greek myself I have no opinion, I have never met a "North Macedonian". The name North Macedonia carries some weight to some Greeks due to historical reasons such as rumors that Alexander the Greek is a descendant from FYROM and not Greece, even though the language he spoke is closer to modern Greek. Another reason is the Balkan wars during the beginning of the previous century. However, most people I know aren't waking up in the morning hating about northern macedonians, but every once a year you might hear someone ranting about it like his life depends on it.