I interpreted it as a criticism of those who think there's no point to learning something if there isn't an immediately-obvious application for that knowledge. Like those who say, "What's the point of learning history? I'm not going to become a historian," as if learning needs to have a clear end-goal or else it's useless. Or those who think it's pointless to learn to play an instrument because you're not going to become a famous musician. It's a mentality that ties in with capitalism, where if you're not being productive, you have no use.

A well-rounded education should equip students with skills they can apply independently no matter what they do. Learning history provides context for the world we live in, why it is the way it is, and can inform us on how to move forward. Learning to play an instrument builds new connections in the brain, strengthens fine motor skills, and (in the case of reading music) how to move information between abstract concepts and a tangible form.

These skills provide benefits to people that can be built upon in the future. They may not have immediate usage to a student, but they create a foundation upon which a student can reach higher as they progress in life. Not every lesson is practical in the moment, but that doesn't mean it can't have value to a growing mind.