There's lots of "could have", but there are some cold, hard facts:
* One of the duties of the duties of man management is to ensure your staff are functioning correctly (not just meeting targets, but that they are not overloaded to the point of breaking them). If you don't believe someone is capable, you performance manage them (and either improve them or fire them).
* The man had proved that he was eminently capable, by performing very well in similar roles at other companies.
* His family had correctly identified that he was suffering from comorbid anxiety and depression and referred him to the doctor.
* He had stated that his boss didn't like him (indicating problems with management).
As he had been performing extremely well, in well managed environments, then he is shown to be capable.
As his family had identified this, it can be considered that he was dispaying symptoms serious enough that any person who dealt with people as a profession could have determined that there were serious problems.
As it could, and should have been identified by management, why wasn't it? This is either a case of incompetence, or negligence. Either one leaves the company culpable, as management are there to act on behalf of the company.
If it was identified, but company culture is to burn up and hire again, then this needs to change, or this will happen again. Legal action in this case is extremely well supported.
If company policy isn't to run employees on maximum burn all the time, and this was a management failure, why was this manager in post if they were incapable of performing a core function of their job? The company hired them for this, so they take responsibility. Again, company culpable. Management isn't just about calculating figures and generating reports. If that's all they test, then they need a wake up call. Heavy legal case would help them re-evaluate.
I've had an episode very similar to this, and was very well on the way to "taking the 'easy way out' too". Management caught me in the spiral, brought HR in, and supported me though a heavy cycle of medical treatment and an analysis of the role, to bring it in line with what is actually workable (the role wasn't possible, though that's not how it was advertised to me before I joined). That's management and company working how it's supposed to work.
I'm definitely with you that the west lives to work though, in the main.. I've travelled a fair old bit myself, and consider Western values to be very skewed. But I'm very much of the opinion, from available information, that the employers have failed in their duties.