I know that it is considered hip and cool to bag WWE these days, and minimise Vicne's contribution, but WWE would have survived long-term, and WCW would have gone under regardless.
On the Austin podcast, when Vince McMahon was the subject, Vince made a very interesting point. The reason that WWE succeeded where the terrortories failed was that the owners of the rival companies put most of their money in their pocket, after expenses. Vince said that he put most of the money they made back into the product.
The fact is, WWE makes more because it spends more. You need to spend money and make money. Good marketing is making your product look visually as attractive as possible. WWE were the first to light up the area, rather than have a darkened room. Now, someone who is sitting in the front row of a show can ask their family and friends to watch, to see if they see them in the crowd. Also, making the area look full looks better than darkened arenas with papered-up seating areas.
Say what you want about Kevin Dunn, he does at least one thing right. He is in charge of set design, and the set pieces look brilliant in WWE, whether it be a row of ladders going down the walkway at "MITB", or set pieces like cars on stage or other props, their set design is A-Grade all the way, admit it. A WWE show looks good and "big-time".
Also, WWE changed with the times. It went from the Hulkamania era, it had the "Attitude Era" and now it has the PG era. WCW did the same thing over and over. Outside of the NWO, WCW didn't really have many memorable eras during the Monday Night Wars, and a lot of shows seemed to be the same.
Also, WWE created stars. They established a lot of their own stars, like the Rock, and made superstars out of WCW talent who didn't have much of a WCW run. Terra Ryzing became Triple H, "Mean" Mark Callaway, who was just another big guy, became the Undertaker, the most successful gimmick wrestler ever. "Stunning" Steve Austin was a moderate star in WCW, but became mega-huge when he was "Stone Cold" Steve Austin. The only original "stars" WCW had were DDP, Sting, Ric Flair, Booker T and Goldberg. All the others were superstars in Japan, or other places first, or even in WWE.
Also, the difference between Ted Turner and Vince McMahon is simple. WCW is just one of Ted Turner's investments. It is easy for someone else to come in and dictate WCW's fate (which is what happened with AOL/Time Warner), whereas Vince invests his own money into WWE, and he is also the owner, so no-one can come over the top and dictate to Vince the direction of WWE.
WWE also has a number of revenue streams, so if one fails, they have many others to generate money from. WWE gets money from live audiences, tours, TV advertising, sponsorship, promotion, merchandise (T-shirts, toys, video games), film, investors etc.
Now, WCW did that too. It is more a problem that TNA have, and why WWE beats it every tme. TNA don't even have merchandise. They once had a faction called the "Main Event Mafia", which could have taken off, but there were no T-shirts made of the faction. Ditto with "Aces & Eights". People didn't buy merchandise because they didn't put any out. The last time TNA put out a video game was back in the PS2 days.
People here bag Vince, but they underestimate him, and that is another reason that WWE survives. When WCW went to war with WWE, Vince brought his A-game. The product isn't as good now, because it doesn't have to be, in Vince's mind. But if there was another legit challenger, Vince would pull out all the stops again. Vince has the bullets and the bombs, he just decides when is the best time to use them.
So, I think that WWE would be around regardless. People have been predicting WWE's death for years, and it hasn't happened yet (the 1995-96 period was worse than the current era is). While WCW and others fall over, WWE goes from strength to strength, and will continue to do so, I imagine.