The piece might be beautiful, it might be impressive, it may tickle our ear or inspire our imagination. But harmony will not inspire joy, hope or fear. It is simple inartificial music that moves the soul. Music should not only be heard, but felt . Complicated music loses the power.
Harmony destroys the power of music.
The power to move people is in the melody. Singing should be congregational not choral. Music is for the people, not the performers. When a group of 12-14 people hog all the singing to themselves, shutting out the congregation, it robs the people of the opportunity for expression. Music is for the people, not to be performed for the people.