YouTube Music makes the strongest early shortlist for people whose music habits already overlap heavily with YouTube and who often look for hard-to-find versions rather than just the standard album release. Those are the users most likely to feel the service's strengths quickly rather than having to talk themselves into them.
The opposite test matters just as much. YouTube Music is usually a weaker first choice for listeners who want the cleanest classic music-library workflow or who do not care about videos, remixes, and YouTube crossover. That does not make it bad; it just means its strongest arguments are aimed somewhere else.