As a teacher I have been asked many times by parents if their child has “got it” or if music is just a waste of time for them. I would usually say whether they have “it” or not does not mean it is a waste of time at all. They’re really asking if their child has a natural talent, and the answer is sometimes.
There are no doubt more naturally gifted musicians than others, but this is by no means definitive or predictive of their future success as musicians. Naturally talented musicians can be undisciplined in practice as things come a bit easier for them or they may have other interests or skills they may wish to apply their natural propensity towards.
A less gifted but passionate musician may practice harder, focus and stick with their work which may in the long run give them an edge or unique sound. Who’s to say what is the right answer, except to say a struggle with music does not necessarily mean a failure of music but rather an opportunity to overcome.