The U.S. has a strong free enterprise foundation and its laws reflect this. Freedom of contract remains the rule even though it is much criticized in some circles and has been hedged considerably over the years. In employment, the old rule was that you could pretty much fire anyone at will for any reason and, if you did, you incurred no legal consequence. This is pure freedom of contract. In time, this unrestricted freedom came to be deemed repugnant where it bumped into important social policies - for example, that employers not discriminate on the basis of race. Hence, protective laws were passed and these circumscribed the old unrestricted freedom to have pure at-will employment relationships that gave an employer an open ticket to fire people for any reason whatever, even a repugnant one. That said, however, when you get down to the day-to-day employment relationships that most of us encounter, the at-will rules still prevail and, with limited exceptions, it really does remain the case that most people can be fired for any reason at any time and almost always without legal consequence. This may be seen as good or bad but it is the way of life under U.S. law with its strong bent toward free enterprise and freedom of contract.
The same pertains to overtime rules for employees. The U.S. does have a body of protective laws that require employers to pay overtime for excess hours worked, either by the day or by the week. But the historic relationship between employer and employee had a strong bias toward freedom of contract - that is, if an employer and an employee agreed to a certain working relationship, that was their prerogative and the government had no say in the matter. Again, this older form of unrestricted freedom led to consequences deemed repugnant as a matter of social policy (e.g., sweatshops). Thus, laws were enacted to abridge the older unrestricted freedom of contract (wage and hour laws, in the example considered here). But, as in the case of at-will rules, these laws did not disturb the large measure of freedom of contract that formerly prevailed except for the specific situations where a policy judgment was made that the workers were most vulnerable and in need of protection. Thus, U.S. overtime rules apply without question to low-skilled jobs and to low-paying jobs and to jobs where the employees have little or no independence or control over how they perform their duties. But these protective rules can and do peacefully co-exist with an equally important set of rules providing that high-skilled employees, skilled professionals, employees with substantial administrative responsibilities with managerial functions, and like positions are expressly exempted from the overtime rules. The idea is that, in a free economy, as a matter of policy, it is better for parties to retain freedom in defining the work requirements of a position than for the government to dictate protective rules where the parties are not deemed in need of protection. In other words, the employer-employee relationships for such exempt categories are deemed to be healthier if the parties are free to negotiate salary/bonuses or other compensation that is not tied to rigid rules about overtime. The laws let the parties have much more flexibility in deciding how to frame their relationships, and this basically reflects the old-style freedom of contract that has always characterized the U.S. economy. Protections were adopted as deemed necessary but they are limited as a matter of public policy. This can be seen as good or bad but it is the law in the U.S.
What does this mean in practice? It means, for example, that a computer professional can be paid a salary of $100K/yr and be asked to work like a slave, all without overtime compensation. But that same professional, if paid $30K/yr, is required to be paid overtime for excess hours worked, even if that person is on salary. One case is treated as appropriate for free choice by the parties without overriding restrictions; the other is not. And the difference, in this case, turns on the amount of salary paid - the highly-paid worker is treated as being able to protect his own interests while the relatively low-paid worker is not.
Europe clearly has taken a different approach and this too can be seen as good or bad depending on one's perspective. In general, in Europe, the idea of open-ended freedom of contract is suppressed in favor of more sweeping protective laws favoring employees. Whether this leads to a robust economy or chokes enterprise is open to debate but it clearly differs from the U.S. approach.
In this piece, the author criticizes the U.S. employment pattern as, in effect, requiring exempt computer professionals to work for free when they are required to work excessive hours tied to a fixed salary. In making this point, the author admits that his European biases are showing. The "U.S. view," if I can call it that, is not that the worker is being made to work for free but rather that the worker has not agreed to be paid by any hourly measure but rather for an overall performance to be rendered, no matter how many hours it takes. This might be regarded as "slavery," but (taking, for example, the exemption for executives) does anyone really believe that top executives have as their focus the exact number of hours worked as opposed to broader goals related to their job performance. The same can be said of professionals, as many computer professionals look primarily to the task and not to the hourly measure as the mark of their jobs. In my field, lawyers too see the hours worked as entirely secondary to their jobs. For every such executive and professional who would be deemed "helped" by overtime laws that might be extended to apply to their jobs, there would undoubtedly be many who would recoil at the limitations of suddenly not being able to do their jobs without regard to the scope of hours worked. I don't believe that most such employees see their work as "slavery" when they have to work excessive hours. I think they see it as career development. And, in any case, the U.S. law gives such employees freedom to become "slaves" if they so choose for their own reason. It is the old freedom of contract and highly skilled, highly compensated workers in the U.S. retain that freedom to choose, as do their employers.
Work-life balance is very important as well, a point the author emphasizes. He seems to have made that choice later in life (as did I) and I commend him for it. But, while I can exhort others too to strive for such balance, I will not begrudge them the choice to work exceedingly hard (especially as they are first developing in their careers) to achieve other "unbalanced" goals. People do accomplish insanely great things by working insanely hard. If they choose to do this in their work as employees, that is their privilege and, as long as they are highly-skilled and highly compensated, I say more power to them if they do it without the benefit of protective labor laws.