There are, but classical music has a more complicated way of cataloguing songs because of the way the data is presented. Some songs are recorded by hundreds of different ensembles sometimes with different arrangements. Not to mention some pieces are known by different names internationally.

All of the Classical offerings are in the Apple Music app. Classical compositions are organized differently than modern music. Instead of an artist->track paradigm, you may have the same composition with a different conductor, orchestra, date of performance, etc. For classical listeners the main Music app's search and library model aren't a good fit.