I consider loyality to be a very desirable character trait. It's very unfortunate if it gets wasted on trash. The opposite would be a woman who leaves her partner the very moment something better shows up. Aka Hypergamy. I suspect that the later kind of women, the treacherous ones always looking for something better, prefer men who believe that they must become an ubermensch just to be good enough. Whereas loyal women most likely just stay with whomever fucks them first and doesn't leave.