Real talk, yeah, there are certain cultures where women are generally like that and women have as much liberty as men to sleep around and be choosy and as shallow as any person can when selecting a partner, or at the very least, a purely sexual one.
But I think it's a mistake to generalize an entire culture like that, and when I say generalize, I mean just labeling that culture with words like shallow and promiscuous. Rather than a specific culture, I'd rather say it's about age or to be more accurate, maturity. Young people are factually generally powerless and will act selfish and stupid due to simple biology and the cultural norm they themselves established for their age group, and this is frankly an impulsive and stupid age group so the standards they set on themselves will reflect that. This is almost true globally except for countries that restrict personal freedoms.
People generally tend to become better human beings as they age, or to be more accurate, they become better equipped and capable to become better human beings as they age. They don't always take that road to become better, but the more information you have around you including personal experiences, assuming the person is living in a somewhat normal environment where there are real choices, the more the person becomes aware of the "correct" decisions.
That's why I second the opinion that whoever thinks Musubu should have left him is coming from people who are either trolling and instigating, or coming from sincere people who are still in the thick of that stupid age group because that's just how it is in their current world.