Where is this concept now? Is creating a family just simple social expectation and not required anymore to be happy and successful in life? Can young (and not so young) folks just live separately - better and easier, with no commitments?
In the past 30 years, family values have changed a whole lot: people are not eager to get married or have children.
Living alone has become simpler and more profitable and now there is more of a chance to find yourself in the world and to only have to pay attention to your interests. An exciting hobby or job, travelling, meeting as many partners in life as one wants?
Now people have a lot of alternatives to the marriage: like guest marriage, free relationships, "friendship with benefits" and so on. And apps like Tinder have made the search for a partner as simple as possible.
The quality of the relationships has changed in the last decades: people get interested in each other and forget about each other very quickly.
Lastly comes the most popular question, “Who will bring me a glass of water when I’m old?” But it doesn’t make people want to have children anymore. Children and relatives will likely be replaced by nurses - because even now, nursing homes are full of old people who have children and grandchildren.