ECW was never really mainstream. in fact, publicly they were all about being "counterculture" and at the time, they were. a lot of what they did was absorbed into the big two's programming where it was first seen. the mainstream is mostly only hearing about ECW in the last few years, after the fact.

basams may have a point. Nitro probably did expose more people to the lucha style. I'm not sure how well the AAA ppv did. I do know that in the early nineties AAA was making inroads into the american market (mostly california, I think) and doing pretty well before they got cherrypicked by WCW.