It's still considered normal for a pony to nap a few minutes every couple of hours, and getting themselves some deep sleep. So much so, they could be considered polyphasic just like their ancestors. Earth Ponies mainly still clung to old sleeping habits, and are considered the most productive ponies because of it. They're the only ones who don't require much sleep at all, despite societal progress over the years. They can even get plenty of rest just by standing, and not moving.