While I agree with the statements in your answer, they are not the whole story.
If the complete answer to "How to find what I am good at?" would be "You are a malleable ball of clay", then what? Go for whatever seems tempting? Go for becoming a rockstar? You might answer "If that is what you really want". Then we are back to OP's question. The shiny rockstar career might seem tempting for a few months or years. And then frustration kicks in like for 90% of wannabe rockstars.
The question what path is the right one for a person is still legit.
Although it is tough for an individual to find what they click with, it's even harder for a third party. So the only advice people can give you really IS "just try things until you find what works for you". I mean, it's doubtful that if you forced a person to try something new, they try something that they know they will absolutely hate.
Also, "Be a rockstar" is not a smart goal to pursue (in that it has a high probability of failure), but playing an instrument with some level of mastery is. If you base your satisfaction on goals with a strong degree of randomness or innate ability to their achievement, you will probably be unsatisfied. Better to base goals on things you can (almost) fully control.
If the complete answer to "How to find what I am good at?" would be "You are a malleable ball of clay", then what? Go for whatever seems tempting? Go for becoming a rockstar? You might answer "If that is what you really want". Then we are back to OP's question. The shiny rockstar career might seem tempting for a few months or years. And then frustration kicks in like for 90% of wannabe rockstars.
The question what path is the right one for a person is still legit.