I don't think automation is the reason for why there's a lack of job and I don't think it will mean there won't be jobs in the future. If we don't have increased demand alongside increased potential for productivity, sure, but is that really reasonable given our love of cheap shit? And even then there is nothing saying we absolutely have to stick to a 40 hour workweek. Wages cannot be dropped (yearly wages, not hourly wages) but due to greater productivity there is no reason not to pay an employee the equivalent of doing a 40 hour week in 1990 for working 30 hours if said employee is as productive as the 1990 employee due to gains in technology*. There is also the point that as one sector shrinks another sector can grow. It might require retraining and a different approach to education, but this is doable (and has been done in the past).
*adjusted for inflation, of course.