I worked nights for 4 years and always needed 9 hours of sleep to feel good, now I've transitioned to working days I find I can easily live on 7.5 hours and be more productive!
Sleeping is very important because sleep makes us fresh but most people don't realize this. During the covid-19 days, i also got this bad habit for staying up for late night which eventually effected my daily tasks.
Whatever you are doing in life and no matter how busy you are, you should take minimum 6 - 7 hours of sleep.