Why Can't Physicists Decide if Warp Drives are Real?

In the years since Miguel Alcubierre came up with a warp drive solution in 1994, you would occasionally see news headlines saying that warp drives can work. And then a few months later you’ll see that they’ve been ruled out. And then after that you’ll see that warp drives kind of work, but only in limited cases. It seems to constantly go around and around without a clear answer. What gives?