How do you know music in the 23rd century won't sound a lot like songs that are 300 years old?
Pro tip: it probably will.
There is a point at which an art form breaks beyond the confines of the zeitgeist. There's a growing number of musical anthropologists that believe it's about there. Because musical taste doesn't change for its own sake. It changes to keep up with socio and technological evolution. But we've near reached the point where it doesn't have to anymore.
Classical music isn't a product of artists of the 18th and 19th centuries, it was a product of the technology and social structures available to them at the time. The exact same can be said for the Beatles in the 60s, Bowie in the 70s, and Duran Duran in the 80s. But we've reached a point where musical instrument innovation has become mostly stagnant. And many believe that we're about there for digital applications. And - globably speaking - socio and political restrictions are much less impactful.
To wit, we're at a point where there's no reason for music to evolve beyond experimentation. And experimentation can only go so far, especially with something as subjective as music where people tend to fall back on what they know. And the I V vi IV songs aren't going anywhere any time soon.