Backstory is as important as your DM makes it. Or as much as you invest in it. And some backstories could use some more investment. Especially ones that are only 9 words long. Of course if you're going for a one shot a 9 word backstory might be all you need to get through. That said if you're writing a short story for your backstory when you're playing in a one shot you may be into overkill territory.