As long as careers are determined by the employer, and as long as careers are the only way to the higher paying jobs, the employer is going to require as much investment from the workers as possible, and will find people willing to give that investment. The employer doesn't give a damn about work-life balance. As long as he finds enough employees willing to give up their free time, flexible working time won't develop ; as long as the employer-employee relationship is one of subordination, it is the employer calling the shots.
To change that, you need to change the balance of power between employee*s* and employer*s*. As long as there is an oversupply of labour, the balance is in favour of the employers - compare with say Crazy Horse or Sven, who have very rare and sought after competencies and could easily negotiate terms of employment if they were to seek a permanent "job".
As long as there isn't full employment, increasing the labour supply is a bad idea and needs to be justified by gross discrimination - sex or ethnicity are gross, asking over 65 to leave the labour supply to get their pension isn't. Un roi sans divertissement est un homme plein de misères