The idea of needing to be married, have a house, have kids by a certain age is unrealistic and idealistic right now. These kinds of expectations give people something to measure their life by, but why? In the past, sure this made sense given the relative closeness in price things were, but now there are big price differences with regard to each.
Marriage requires commitment, respect and money. Diamonds ain't getting any cheaper. A house especially on the coastal states is unreachable for the typical and it gets worse every year. Raising kids is expensive. Do you really want to do or obtain all of this by age 30 or 40? Yikes!
Capitalism, regulated, instills a sense of independence and fairness, but unbridled capitalism induces slavery and predatory behaviors. You can't reach life goals under unbridled capitalism because nothing seems fair. You work work work, but the reward you get does not appear or isn't commensurate. When market players feel they are being played they step back from the market and take less risks. Market leaders are players, but don't play at the same level or rules as the other players. Because of this, players gain a negative view of said leaders. If the market is to be trusted again, the leaders must sacrifice or be sacrificed for the common good of the market.
Sacrifice means redistributing means of trade in a market so players feel good about joining again. Getting back to participating and setting life milestones to make sure the market can continue.
As long as the market is disproportionately unfair or distributed poorly, life related age milestones are useless. The measurements people use with regard to these milestones just don't matter.