The world of work is vastly different.
Zero hours jobs or jobs with minimal hours guaranteed, don't offer stability or promotion prospects.
The idea that if you work hard, you'll do well is long gone.
Many of those on the lowest incomes have unstable employment prospects, short term tenancies, have little access to extra tuition and, with unstable, 'as and when' hours, are unable to commit to evening classes, social events or any regular activities.
I'm lucky, in that my mortgage is paid off, but I've lost out on opportunities as I can't afford to turn down work or have committed to shifts I can't then cancel.
Children growing up with parents scrabbling around for relatively menial work and the ever present prospect of losing the roof over their heads, tend to follow their parents into low paid, menial work, as they don't have the opportunities available to children of parents in regular work, who can schedule their lives around working hours and who can help their children with homework, extra tuition or school events.
Children see the fight for money and accomodation prioritised over their education and learn that lesson very early on.