The Attitude Era would be very hard to be duplicated.
1. You had the rise of the Internet, which led to the breaking of the longstanding wall of kayfabe. It was a major novelty when you would see that fourth wall broken down at the time. Today, it usually looks forced. You also had constant discussions about wrestlers' workrates and analysis of matches, storylines and bookings.
2. You had the Monday Night Wars between WCW and WWF. Two live TV shows, going head-to-head with each other. Each show was doing all they could to top the other one, at least until WCW got stale.
3. There was the rise of the 'cool' heel that was getting cheered while beating up the babyface. Austin, The Rock and the NWO all were among the most popular stars. Even when they would turn good (in Austin and Rock's case), they kept their edge (no pun intended). Today, you have Cena, who has lost all his coolness (his rapper image).
4. The WWF's sex references were pretty novel at the time, although I remember thinking to myself that someday, they would wonder what they were thinking about.
Unless a new, and strong, No. 2 show were to emerge, and different technologies, it would be pretty hard to duplicate the Attitude Era. There might be a similar one, but nothing close to the original.