The problem is that we keep raising the floor on the level of training and aptitude that's required to be a productive worker in society, and we're already getting to the point where a lot of people can't keep up. The shift from being behind the plow to a cog in an assembly line doesn't filter that many people out. The shift from blue-collar industrial to white collar bullshit clerical employment filters a little more, but the shift to skilled knowledge work, which is rapidly becoming the only path to economic security, filters people hard. There's a lot of people that don't have the tools to even compete, and more that have the ability but don't have the resources to retread.