Tech companies don't give their workers flexible schedules instead of pensions because flextime is more valuable than a pension. They give them flextime becaus

Tech companies don't give their workers flexible schedules instead of pensions because flextime is more valuable than a pension. They give them flextime because (a) it costs them nothing (b) it has no impact on the quality of the work done (c) flextime workers are just as if not more likely to overwork and (d) it costs them nothing.