It hasn’t become a common practice for both genders to wait before settling down. That doesn’t have a thing at all to do with the relationship per se.
If people from both sexes decide to wait before moving a relationship forward, it’s usually for some specific reason to be honest. It could very well be that either the man or woman doesn’t want to be rushed into something that they aren’t yet ready for. Another factor could be that they still feel that they need to get to know the other party better before making any commitment of any sort. There are lots of reasons why people decide to wait no matter if they are male or female. Gender class has nothing at all to do with it. The many reasons could be anything from emotional to financial to what not? The sky is the limit on this one as it could almost be any valid reason why not to decide to settle down right away.
Time is a crucial factor when two people are getting to know each other, so people should take the time and take advantage of it before deciding to settle down with each other. Because, if you rush something too fast and it’s not meant to be, that’s what will end up happening.