I totally agree that a true professional approach is view it as a job rather than an creative or inspirational outlet in your life. And I follow this approach. I see it as a marathon rather than a sprint.
That said, posts like this are common on HN. People burning out and get disillusioned with their jobs. Or loose meaning in tech.
Could this be because 15-20 years ago in order to get in to the industry you had to have a certain passion and curiosity in order to get through the forest of very technical tools and programming languages in order to run anything. Industry was not mature and there was a lot of hype around it's wins, it was literally changing the world. Software was eating the world quickly. Books like "Passionate programmer" and "Secrets of the Rock Star Programmers" were promising us the land of endless rewards if we pour our whole selves in to the job and forget about anything else.
But nowadays, 20 years of growth, billions of LOC and millions of people came in to the industry. Now we've got the understanding that it was just a job after all. And instead of pouring your self in to it, the sustainable way is to treat it like a job and also have a life outside of it. Hedge your bets if you will, because life is more than tech