This is terrible advice in the general. I've known lots of people following this advice, to peruse a career in a field that doesn't really pay much. Ended up struggling and stressed.
I feel really sorry for you and your friends who spend your lives doing what you don't enjoy for the sake of some 0's on your bank account. Also, I'm not saying go pick flowers for a living. But you should at least enjoy what you do, which fosters continual growth (to become an expert, you must grow).
Most people don't enjoy struggling and the stress of not being pay the bills.
Trust me, that's more stressful than a job fairly your fairy 'meh' about. It's much more likely to burn you out.
Most passions, when you turn it into job, just ruins the passion(Having done this myself). You go from something that's creative into something where cost, and timelines matter and you have very little personal input.
I understand where your coming from and I'm sure theres a happy medium. Doing just money or just enjoyment wont work as well as a proper balance.
But, to play devils advocate... Having worked in a high paying, crap job and moving into a job with lower pay but much more aligned with my passion I am MUCH happier