Guy is correct on this point.
The revered composers like Bach, Beethoven and Mozart are comparable to other composers in a way similar to an atomic bomb compared to a firecracker. Every one of the less-known composers mentioned in the other post probably worshipped Bach and Beethoven. This doesn't mean that dry recitations of their greatness in a dull academic setting are good, but those composers are not reducible to the uses to which they are put by college professors. To me, they still live whenever their music is played.