Really? I'd say we have an easier time accomplishing this than a medieval peasant - if we wanted. I'd buy it if you told me people chose not to live this way - but i don't think it is any more difficult to live this way.
In many countries youth unemployment (not occupation, but actual unemployment) is 10%+ sometimes it reaches 50%.
How you can marry, if you have no money to do that, and the law is against you? (with harsh penalties for divorce, but at the same time divorce is easy and encouraged, making marriage inherently overly risky).
How you can have kids, without money even to feed yourself?
I know plenty, plenty, plenty people with 25+ of age, that don't own anything, no car, no house, not even a bike, how these people can even consider having kids? Who will take care of them? Orphanages? The state somehow?
It's pretty easy to be sucked into a "things are bad" narrative, but plenty of people get married at much worse poverty levels (especially historically).
[1] http://www.tradingeconomics.com/united-states/youth-unemploy...
[2] http://www.tradingeconomics.com/united-kingdom/youth-unemplo...
[3] http://www.tradingeconomics.com/euro-area/youth-unemployment...
Also, if you look at your links and click "max", although things have improved since 2010, they aren't that good, specially when you consider also other factors.
For example, the percentage of youth forced to live with parents keeps increasing:
https://www.census.gov/hhes/families/files/graphics/AD-1.pdf
In many countries, there are large amounts of fatherless children, for example black children in US was about 73% of them being fatherless.
Some countries still have devastating amounts of youth unemployment, Greece for example right now is 46%
http://www.tradingeconomics.com/greece/youth-unemployment-ra...
Also, although now everyone is "wealthier" because random stuff noone needs is cheaper, living costs keep rising, for example health care costs, housing costs, and in many places food costs have been rising faster than both inflation, and income.
Brazil for example is having constant strikes since about 10 years ago, even during economic boom, with people upset with food costs, frequently strikers instead of demanding higher wages, they instead demanded more food-related benefits.
Food prices in Brazil rose 173% in the last 10 years, while inflation was 122% and wages rose 68%.
And yes, it is easy to get sucked into "things are bad", when they are. At least to me, and almost every single friend I know.
edit: removed excessive personal information.
In that case you should compare properly:
English kept their children at home "till the age of seven or nine at the utmost" but then "put them out, both males and females, to hard service in the houses of other people, binding them generally for another seven or nine years"... most parents waved goodbye to them at about 14... Illiterate servants had no means of communicating with their parents, and the difficulties of travel meant that even if children were only sent 20 miles (32 km) away they could feel completely isolated... adolescents were a useful source of cheap labour for their masters. In 1350, the Black Death had reduced Europe's population by roughly half, so hired labour was expensive.[1]
Doesn't sound too awesome to me.
"In many countries, there are large amounts of fatherless children, for example black children in US was about 73% of them being fatherless."
And in Iceland over 70% of children are born to single parents[2]. I'm not sure what your point is - this isn't necessarily bad unless you are making a value judgement here?
[1] http://www.bbc.com/news/magazine-26289459
[2] https://www.fatherly.com/parenting-and-relationships/why-ice...