I think they are high control, they do lots of cultish things but people's usual idea of cults is that it's a small group following an individual charismatic leader. They grew past that stage and large enough to drop the label but retail many of the traits, mostly the desire for control.
But use of the word "cult" in wider society has watered down the original meaning. People describe Apple devotees as a cult and so on. So I think to many, the WTS, Mormons and Scientologists are as much cults as they are religions.
Same for Catholics and Islam ... in fact, isn't any religion really just a cult?