or you are compensated heavily based on the company's profit, it is foolish to be engaged in your job.
This is a very culturally relative sentiment.
Being "engaged" in your job means sacrificing part of your life for free to benefit the owners of the company.
That really depends on what you mean by "engaged". I don't think that it has to mean you are putting in free overtime or hustling so much that you burn yourself out. It can just mean that you are present in the moment when you are at "the office". Put in the effort to do a good job, build professional relationships with your co-workers and bosses, try to think about what actions you can take while you are at work that are best for the company... and then leave that all at the office when you go home so you can focus on the rest of your life.
Your job is not your life.
If you're a regular 9-5er you're going to spend a third of most days at your job, or half of your waking hours. Your job is not your life, but it would seem to me to be a terrible waste to be checked out of half of your waking hours. I believe that you are primarily cautioning against folks who turn their job into their WHOLE life. Live at the office, make it their identity... and I totally agree with your warning. But I think the attitude you're advocating for is just a step too far.