What the statement means is that writing should not come easy to the writer. Genuinely raw writing isn’t something that can be easily created in a matter of minutes or hours. If it was, then everyone in the world would write whenever they can. Writing is hard for the very fact that it is difficult to confirm your emotions and find the right combination of letters to fit onto a page in order to express those feelings. Writing is hard for the very fact that the writer is allowing themselves to be vulnerable and open by pouring their souls out onto paper with ink. Writing most certainly isn’t easy and it’s a falsified myth if anyone has ever said it is.