A lot depends on the circumstances around the times you DO write/create. Are they days off from work? Does inspiration strike at 11pm? Do you need absolute silence, or sitting in a busy place (like coffeeshops used to be). The "write every day" advice it about building habit

So in that sense it isn't on the wrong track, it's just trying to shoehorn everyone onto the same train. You DO need to build a habit around writing but tailor it to HOW YOU ACTUALLY WRITE. 3000 words every Sunday? then that's your habit.

Only write after coming home from parties at 2 am? That's your habit. You might have different habits for original vs. fanfic (I do). You might write in disorganized chunks randomly by hand, but then transcribe to computer twice a week. Doesn't matter.