That statement "apostates can only criticize, tear down, and destroy" is the last refuge of someone who cannot compete in the marketplace of ideas. When a Witness makes such a statement, he has conceded the argument.
Fact of the matter is that if you really want to believe something, you're going to find a reason to believe it even if all the available facts point in the other direction. Nowhere is this more evident in the area of religion.
People are scared of the dark and don't want to die. The Witnesses (and other end-times hucksters) tickle their ears by offering "Millions Now Living Will Never Die" in a nice little package. Some people are gullible enough to buy into it. These people are not going to be dissuaded by facts.
Some of us prefer the real world. With all its flaws, at least it's real.