I think there are several reasons to this answer not being answered anymore by Daedalus.
First off, he's said it quite a lot of times, and his answer has been the same every single time. If you had to answer '2+2 = ? ' 50 times during math class, and every time, it's just '2+2 = ? ', I think you'd get bored and annoyed pretty fast. Same with this question; it's the exact same every single time, and the answer has been the exact same, every single time.
Adding to that, there is no set ammount of players needed for a Hero world as far as I'm concerned; Daedalus could start one with only 500 players - sure, hooray, we'd have a Hero world. But after 2 weeks the world would close because it dropped below the minimum of 300 players per world. And, of course, if that happens, Daedalus would get a spray of mean comments, questions, and what not. I think this is one of the main reasons he's decided to get a large ammount of players with the award first before opening up a Hero world, or even considering to open one.
We all want a Hero world, but asking when it's going to open, is just as futile as asking what time a new server will open; Daedalus will let us know when it does, when it does. Asking won't speed up that process.
Don't get me wrong, I want a Hero world to open up, too. But I'd rather have a Hero world open up with 50.000 players joining and some serious competition, than a Hero world opening with maybe 2000 players, and nothing to do but play SimCity because there is no one to fight.
PS: Just because someone has the award, doesn't mean the player will join a Hero world. If there are 100.000 players with the Heroic Tactician award, I think there might be 40~60% of that joining; some of the people have quit, or aren't interested in Hero worlds in the slightest