A career ending mistake
I changed careers at 40+ years old.  I'm very happy that I did it.People have all sorts of constructs / ideas about how careers work (based on experience) or how they think it works, or how they want it to work.   I talk to some college graduates who tell me what they're planning for and have ZERO clue what industry they're talking about, their description is unrecognizable to me ... even tho I know it is the one I work in.I find your experience and paths can vary greatly company to company, even job to job.We all find truths we want to hold on to about work.   I recall trips to the valley where my coworkers where astonished to hear tales of people doing the same work they did, but doing it slightly differently elsewhere in the country.  Their view of how that job was done was entirely shaped by the couple places they worked (and everyone seemed to cycle through those couple companies).   You'd think these folks though that if you didn't fill out the TPS report right to left that the world would end... I'm pretty sure the vast majority of people fill them out left to right but I didn't feel like telling them that, it might have been too much for them to handle."
I think there are three main kinds of career destination, at least in the tech industry:    Independent
    Senior individual contributor (IC)
    Management
"I have no idea why those are the only destinations ... for an article worried about being happy that seems kind of limited.The whole article feels very pie in the sky to me.