It's perfectly fine to leave your Xbox One on all night if you're using it as a console. However, if you're using it as part of an entertainment center, it's not recommended. The reason being is that the Xbox One has a number of different power options, and when left on overnight, it will automatically go into low-power mode. In this mode, the console won't provide background updates or download content. So, if you're using your Xbox One as part of an entertainment center, we recommend turning it off at night to avoid any potential issues.