Personally, I think I would have still been a wrestling fan, but I can't be sure. I never watched WCW when it was on. I was a hardcore WWF mark and was exclusively loyal to their brand. But that being said, I quit watching WWE (and all wrestling) for a long time because the show just kept getting worse and worse (not sure the year, but it was a few months after HLA).
Then I discovered old ECW a couple of years ago and started watching TNA last year when they had the ECW guys come in for Hardcore Justice. I have loyally watched ever since. I've tried to watch WWE again too, but now I find it really bland and I can't get into it.
Odds are If WWE went out of business, I would have given watching WCW a try and as long as they didn't do something horrible like WWE did (HLA, Kiss my ass club, etc), I probably would have never stopped watching wrestling in the first place. So I'd say yes i'd still be a wrestling fan.