There's only one reason why they would reset the MMO. And no one has mentioned it.
The first thing you need to understand is that they're not dumb. These people are .. NOT.. dumb. This means:
1) They would not pour hundreds of millions of dollars into a game, and wait until the VERY last second to scrap it because they didn't "like it". They would have OBSERVED much earlier that it wasn't headed in the right direction. This supports the obvious alternative...
In reality, the truth is that they were making a lot more money from WoW than they expected they were going to be making at the end of 2013. When the document was leaked years back, showing that Titan had been scheduled for a 2014 release, WoW subscription numbers (in millions) were going down the toilet. Literally. They wanted to have a game ready for when WoW met its end. But, as it turns out, WoW had a more resilient, core player base than people originally thought... and games that were perceived to be threats (ie. Star Wars) turned out to be duds.
It all comes down to profit. How can they make more profit? How can they satisfy their shareholders? 1) Taking a gamble by releasing Titan now (with WoW earning hundreds of millions of dollars each year already) ORRR 2) sticking with WoW for a few more years, and making guaranteed money. The latter of course, was the safest bet. This is why...
Releasing Titan while WoW was still going strong would have been the most stupid decision of the century, because in MMOs, we have something called a FIXED playerbase. People cannot be playing two MMOs at the same time. When you go to one MMO, you leave the other. And often, the number of active players playing MMOs are relatively static. Because they already OWN the majority of the MMO player base, they would only be stealing players away from themselves to feed Titan.
Instead of trying to manage two very popular games at the same time, Blizzard's plan has ALWAYS been to wait until WoW dies to release Titan. It is simply more profitable, and more practical. They have decided to scrap Titan (instead of hold onto it for later) because in however many more years it takes for WoW to die, Titan will likely be behind its time.
The sooner WoW dies, the sooner we get our beloved Titan. Convince your friends to quit.