There is a simple explanation for this move: Moore is simply not an expendable part of the defense; therefore, it is too risky to let him test the free agent market and get away. You can make the argument that the Falcons’ safety duo is one of the better tandems in the league.
Putting the tag on William Moore seems like the most logical of choices at this point. But, you never know. Things can change rapidly in this league. If it were up to me, I would make sure Moore stays put.