I mean people would just adjust to the new time patterns. In every time loop story, people try staying awake past the reset and usually it just resets regardless of whether they’re asleep or not. The exception i can think of being palm springs, where they only reset once they fall asleep or die. But if the reset happens at a constant time for everyone, everyone would just adapt. Day and night already barely matter now that we have electric lighting and instantaneous communication. ‘Days’ would just start at the reset, and either last until the next reset, or 8 hours before it happens, or whatever the equilibrium ends up being. Maybe sleep would stop being necessary for most people altogether, if their bodies’ clocks reset along with everything else. That could be kind of interesting.
I imagine most things would become a service barter situation. Like you make me a great meal and ill give you a massage. Or whatever. People would be pretty confined to a particular region if theyre returned there at the start of every reset, so you’d probably have a build up of a sort of reputation economy. Probably mass marketplaces would form up where people could trade ‘favors’. There’d probably be a new occupation that crops up where someone keeps track of credits and exchanges them, but any kind of physical currency would be useless. But if you wanted a service from a particular person who didnt want anything you could ogger, you’d need some sort of middleman to vouch for you or things could get complicated fast.