For this sort of motor skill, it’s definitely learned. For stringed instruments, for example, it’s the left hand which has the more finely managed manipulation than the right (it’s interesting to note that only guitar-family instruments are commonly made in left-handed versions, although some of that may come down to logistics of string ensembles where having one left-handed violin in the violin section would cause a bit of chaos with colliding bows that is less of an issue with guitar ensembles where there are fewer musicians and they’re less tightly packed in the performance space). Likewise, the fingering on woodwind instruments doesn’t really favor one hand over the other. In contrast, brass instruments are decidedly right-handed (I suppose one might be able to manage a trumpet left-handed, but I’ve never tried. I don’t think other brass instruments could be fingered with the left hand at all.