Relationships with multiple instrument/vocal attributes are intentionally split. It’s for storage purposes.
Not everyone was happy with that change.
Unfortunately the combined display hasn’t been implemented yet.
As a voter I still see people trying to condense them afterwards. I don’t vote against such edits, instead I explain the split is done on purpose. Most of them cancel their edit(s) then.
But for some reason the edit adding attributes for Manfred Mann wasn’t split. I think it’s because dates were added too.