Per this, Ramadan fasting is 13-15 hours per day: https://www.brandeis.edu/spiritual-life/resources/guide-to-o...

Since the non-fasting hours include a night of sleep, that schedule sounds pretty rigorous to me. Americans typically have an eating window of 12-15 hours, eating 5 times per day: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8705992/

The Ramadan fast also includes not drinking any liquids, which many people find to be the most difficult part of the fast, especially considering the types of climate a majority of the Muslim population lives in. It also requires people to be awake during the day to do all their mandatory prayers, so the sleep during the day strategy wouldn’t really work. You basically have to get up for the pre-dawn meal, unless you want to wake up dehydrated from sleeping, and wait 10 or so hours to have your first glass of water. The fact that the dates of Ramadan move every year also means that you’re expected to experience the fasting during all of seasonally different lengths of day your location has (if you live in a place that has no sunset I believe the religiously permissible solution is to fast according to the schedule of Mecca).