If companies are required to pay workers overtime after 40 hours, why are salaried employees expected to work 50-60 hours with no additional compensation?

The Fair Labor Standards Act mandates overtime pay for hourly workers who exceed 40 hours per week, but salaried positions seem to operate in a completely different reality. A friend in tech mentioned their team regularly puts in 55-hour weeks during product launches with zero overtime consideration, while the warehouse workers at the same company get time-and-a-half for anything over 40. Both are doing necessary work for the company, but the compensation structure treats them like different species of employee.

This feels like it should violate the same labor protections, but somehow "exempt employee" status creates a loophole where professionals can be expected to work indefinitely without additional pay. I came across discussions about this in r/ADHDerTips where people were tracking how burnout from unpaid overtime was affecting their ability to function, and it made the inequity even more obvious. The argument I've heard is that salaried workers are compensated for their expertise rather than their time, but that breaks down when the job explicitly requires more time than the standard workweek.

If the principle behind overtime laws is that workers deserve compensation proportional to hours worked, why does a salary designation completely nullify that protection? What economic or legal justification allows companies to extract 50 percent more labor from salaried employees for the same pay that was presumably calculated for a 40-hour week?