Why would a God that gives people free will and wants people to serve him out of love use the fear of dying in an apocolyptic catastrophe to force people to serve him?
The WTS states that its followers serve God out of love. Love for God, love for their fellow humans. But talk to many of the individual JWs and what is their greatest fear? Dying at Armageddon. That's not serving God out of love. That's serving him out of fear.
JWs think that all will be rosy in the "new system". No fear or death. Wrong. God used fear and death to keep them in line before. What will he use to keep them in line afterwards? Fear and death. The fear that JWs have now, they will always have, even if an Armageddon should come.