Lots of bands got lumped in to 'grunge'. Almost any slightly heavy rock band that wore dirty jeans and check shirts were grunge. One of my favourite bands, Blind Melon, get classified as grunge on some lists. Then again, Janes Addiction are grunge according to some. I don't think so. (Neither are STP)
It was the last interesting wave of music for me, perhaps that's my age. It was miles better than Britpop, which was abysmal dross. What irritated me about Britpop was its unfounded confidence and arrogance. The singer from Franz Ferdinand said that Britpop connected better with British audiences than a check shirted rocker from Seatle, utter drivel.
I've just listened to Pearl Jam Vs, a cracking album no doubt.