It is generally believed that people's aesthetic judgment is subjective, and this is true in a short period of time, and people's evaluation of contemporary works of art often diverges greatly  However, over time, the subjective element in aesthetics gradually disappears
When a work of art continues to provide pleasure and beauty over the centuries, as in Da Vinci paintings and Bach's music, we can fairly objectively call it a great work
For the same work of art, people's evaluations of different eras are very different.