I agree entirely with the OP.
Of course JWs are christian. They believe they are ransomed by Jesus' death. The way they explain that is bizarre but it is still the foundation of their religion.
They believe Jesus is the son of god - the trinity is post-biblical - and they claim to follow his teachings in the way they understand them.
Every denomination is on a cult spectrum. JWs are further along that line than many other denominations but not as far as many other groups.
The word "christian" is not a synonym for goodness, kindness or ethics.