Ya i've noticed my 3 heart run isn't doing it as often, but everytime you earn a large amount of money, or get a heart container, it'll remind you to save, I'm not so sure its based on time, as much as you did something it feels might be worth saving.
Oddly enough beating a temple doesn't set it off, unless you grabbed the heart container. Saving a sage not as important apparently.
This is at least the behavior i've noticed.
Yeah, I don't get why the game is trying to parent us with how long we've been playing...
Ya this actually does kinda make me mad, its like
1, why do they care?
2, It keeps counting time even from before when the console was in standby with the system closed
3, you can be playing for 10 minutes after turning the console on and it thinks you should be done.
4, Shut up nintendo, If i want to take a break I will