No sleep for the wicked?

tl;dr it recently came to my attention that there's no requirement to sleep in 5e, so how do you handle it?

I was discussing with a friend the difference between rests and actual sleep in D&D 5e. They were surprised that per the RAW, neither a short rest nor a long rest actually "requires sleep".

Rule's Answers

A long rest is a period of relaxation that is at least 8 hours long. It can contain sleep, reading, talking, eating, and other restful activity. Standing watch is even possible during it, but for no more than 2 hours; maintaining heightened vigilance any longer than that isn’t restful. In short, a long rest and sleep aren’t the same thing; you can sleep when you’re not taking a long rest, and you can take a long rest and not sleep.

Per the RAW then, there's no requirement to sleep during a long rest. You can choose to, but there's no actual requirement.

In my game, I guess as a house rule, I've been treating long rests as the actual sleep cycle for a few reasons. One is to simply help me remember to have the PCs actually sleep. Another is that only a single long rest is allowed every 24 hours, so logically that makes sense to be when the PCs sleep. The rules I've been using are: a long rest is 6 hours of sleep and 2 hours of light activity. If you're an elf, you get 4 hours of meditation, and 4 hours of light activity. Basically elves are better at being on watch. It's a minor perk, but it makes trance slightly more meaningful. The PCs also catch up on sleep during downtime activities.

You might be thinking: the reason there's no specific rules around sleep is because there doesn't need to be -- the DM can just handle it, or not bother with it at all. However, there are rules for not eating and drinking. Food, water, and sleep are a trinity when it comes to basic survival. It seems like an oversight that not sleeping wasn't mentioned in that area.

I'm entertaining the idea that if someone stays up without actually sleeping for their Con bonus in days they gain a level of exhaustion. Then every 2 days after that, gain another level. The current world record is 11 days. So a person with a 20 Con could go for roughly 15 days in game before dying.

If you're wondering: no, I'm not planning to heavily reinforce this! Just puzzling through a gray area in the rules and thought it would be fun to discuss. How do you handle sleeping in your game? Do you use any kind of exhaustion rules if the players don't sleep for a certain amount of time?