I think open world games have this unspoken implication that the world is not merely what's presented in the game world.
Basically the equivalent of "how come I never see my character take a shit" because it happens in the implied off screen time lapses.
A good example of a game acknowledging this is Xenoblade 3, which canonically takes place over 3-ish months because the progression of time is plot relevant. In most cases this is inconsequential and presents only minor plot holes at best. Yes, it's possible for 2 young people to fall in love in 2 weeks, especially when they're bound together in a life or death mission.