I think it's better advice in the long run than most people realize, but it depends on so many factors:
- What your passion is and how realistic it is to live off it.
- How truly passionate you are about it, especially compared to most other people (it's probably easier to be the most passionate carpenter than the most passionate rock star, due to how many people want to be the latter).
- How good you are at learning new things.
- Whether there's any hard cap on how good you can become at it (e.g. I would probably never be able to make it as a professional athlete no matter how passionate I was about it).
There's probably some mathematical formula you could apply to determine if it's worth it for you or not, but in my experience, intrinsic, enduring motivation is a much more important long-term factor for success than many people realize, and certainly more important than just "what you're good at". But it has to be the kind of passion that fuels you to improve your craft over years and decades, and until you're knee-deep in it and with a few years of experience behind you, it's very hard to tell if you're going to keep loving it indefinitely, or if it's going to eventually fizzle out.
Besides success itself, however, there's the question of happiness. Are you willing to earn less and lead a humbler life if that means you get to work on what you really love? Conversely, are you able to work on something you don't much care about, if this means earning more money to lead the life you want in your free time?
There's really no one-size-fits-all answer; a lot of it is about trial and error. But I think, in the long run, there's probably more people that regret not giving their passion a shot, than people regretting doing so and failing. The latter, at least, won't spend their lives thinking "what if..." and sighing.
