We can still produce enough food and stuff to feed and house and clothe everybody. We can still run a growth economy. But we don't seem to know how to allocate resources to people for whom there are no jobs. There's a pervasive cultural assumption that people who don't work are shirkers or failures, rather than victims of technological change, and this is an enabler for populist politicians who campaign for support from the frightened (because embattled) working majority by punishing the unlucky, rather than admitting that the core assumption—that we must starve if we can't find work—is simply invalid.
I tend to evaluate the things around me using a number of rules of thumb, one of which is that the success of a social system can be measured by how well it supports those at the bottom of the pile—the poor, the unlucky, the non-neurotypical—rather than by how it pampers its billionaires and aristocrats. By that rule of thumb, western capitalism did really well throughout the middle of the 20th century, especially in the hybrid social democratic form: but it's now failing, increasingly clearly, as the focus of the large capital aggregates at the top (mostly corporate hive entities rather than individuals) becomes wealth concentration rather than wealth production. And a huge part of the reason it's failing is because our social system is set up to provide validation and rewards on the basis of an extrinsic attribute (what people do) which is subject to external pressures and manipulation: and for the winners it creates incentives to perpetuate and extend this system rather than to dismantle it and replace it with something more humane.
Pointedly, the problem is not "preparing kids for jobs that don't exist yet." There will be many jobs that don't exist yet, but there will not be enough of them to employ everyone, full stop.
Just to be clear, in the medium term, we could get back to more or less full employment with higher government infrastructure and public service spending, but the longer term problem only becomes more clear.