Definitely one of the most influential and important bands of all time and was fortunate to see them twice in 1992. One of the venues had a capacity of 2000 and that performance is in my top 20 all time live gigs. I understand how those that favour other genres prefer the unplugged version of Nirvana's songs over originals. I doubt any Nirvana fan would agree with you, that's why you would struggle finding anyone that wasn't a fan in some capacity.
I doubt any musician in there early 20s would be ''strong enough to be the leader of their generation'', i believe he could of if given the chance to mature. Kurt Cobain did not destroy himself, that discussion is for another day.