I haven't been on this board in awhile and I found this post interesting because I had almost this exact same conversation about a month ago.
There is a saying in the business world that if you aren't moving forward then you are dying. Sadly, pro wrestling is slowly dying and it is evident by the amount of sentiment and nostalgia going in the WWE.
That isn't to say there is anything wrong with nostalgia in-and-of itself, but as thebrainfollower posted, letting it dominate the future is suicidal. I don't watch Raw every week, but it does seem like that when I do I either always hit the nostalgia nights (anniversaries or the back to the 80's night). I think this is because the WWE simply can't produce stars anymore. Cena is arguably the biggest star right now and C.M. Punk kind of floats on the edge of stardom, but everyone else is stuck in the middle. As others have pointed out, that is why the part-timers have to be brought in for the Wrestlemania main events because if they didn't you wouldn't have much to draw fans in for the show.
About 10 years ago, on another message board, I posted that I thought Vince McMahon was turning into Verne Gagne and I was told I was crazy, but as time is passing by I feel stronger that I am correct. The world has passed Vince by and he doesn't know or refuses to change. The domestic wrestling audience continues to hold steady at a fraction of what it once was and rather than moving forward to try to attract new fans they are trying to survive by bringing back the old fans. You can say that Undertaker, Rock, and Brock have become Crusher, Dick the Bruiser, and Baron Von Raschke in that their days have come and gone but they are still being counted on to bring warm butts on to the cold seats.