The second one is not true. Utopia of happiness would result in vast stagnation.
Agitation, annoyance, something needing fixed, imperfection, desire for more / self-improvement, etc. is a critical root of invention and creativity.
Ideally not everyone is perfectly happy all at the same time. And it should be noted that is not the same as saying that everyone should never be happy. Rather, that it's incredibly valuable to have dissatisfied people in society - they're often the ones that break with the status quo and push humanity forward.
When a person says "Not to be x, but", being x is exactly what they are doing. It's wilful self-delusion. Either fully own and accept your decision or, if that's problematic, consider that maybe it's not a good decision and consider an alternative course of action.
If a CEO/hiring manager decides employees that become depressed, get sick, are involved in an accident, whatever are to be shown the door rather than offered help or assistance, fine, that is their prerogative. But don't pretend it's not a shitty way to treat a person.
And employers wonder why so many people absolutely despise their jobs. Treating a person like a piece of equipment that can and should be replaced immediately if a part malfunctions or it isn't performing optimally is an excellent way to ensure an oppressive and hostile work environment. But then you get to crack the whip and scare some "motivation" into the workforce, and maybe that's exactly what you wanted to do. Just don't expect a grateful and productive staff.
Depression in the workforce causes reduced productivity and substantial amounts of money on a national level. The CDC estimations that it causes 200 million lost workdays each year which costs employers between $17 to $44 billion alone. It's in an organization's interest to have healthy employees; both mentally and physically.
Employers have a duty of care to protect their staff from harm in the workplace, and this includes work-induced stress and depression. At least, this is the case in England, and there have been legal cases that support this principle.
There are some elements of "contagion" around workplace stress. Obviously there aren't "stress germs" being passed around, but one stressed member of a team can cause stress and poor peformance in other members of the team.
