Just far too many games adhere to that simple formula. Blizzard reached HUGE success with that - kind of an Nethack clone, as I often said.
What I do love - and I really love oit very, very, VERY much ! - is that the Bard is actually influencing things through Music ! Since Wizardry 8, I haven't seen that. Far, far, far too many games are out there merely sllowing mayhem and slaughter, and not a single game is about music. It's as if music as a gameplay part was an invention of the most evil.
Today, games - and especially most RPGs, and since most RPGs these days are based upon the Action-RPG model - are merely about combat. Battling, swords and slaughter, most don't even offer something more sophisticated that slaghter and maybe some kind of magic.
I bet that most Action-RPG lovers hate The Badrd's Tale 4 for its music. For, as you wrote it, "RPGs should be about killing and levelling up" (my words).
People are I bet hugely irritated by music as a gameplax part. It shouldn't be there, I bet they say. Like zjat enemy in the game already says - oh, what an irony ! - "Music is perversion !"
In the current age of dark, brutal, so called "mature", "heavymetalized" games, a thing like music is simply not wanted. Music is like colours. Music is childish. Music is immature. People want brutality.