Superdelegates are an affront to democracy and should not exist

[Kalimantan]

Theoretically, how would people react if Sanders won the popular primary vote, but the superdelegates made Clinton the nominee?

Won't happen, superdelegates are almost a ceremonial thing, they'll swing whichever way the wind blows. Take 2008. If all the superdelegates voted the way they originally pledged, Hillary would have been the nominee. But huge numbers switched to Obama because he won the popular vote. That'll happen over and again