Ultimately, cult behavior will always be the litmus for what a cult is, whether the primary deity be Jesus or Vishnu. I'd love to say my experience was unique but that doesn't bear out given the plethora of testimony you can find out there. My grandmother herself was disfellowshipped when my grandfather refused to join the JW along with her. He said they were a cult then and maintained that stance until his death, though he just said it because they seemed to demand everyone think exactly alike.

No organization regardless of their views of Jesus should ever encourage a member to sever all ties with family over the family's views or refusing to join. No organization is above judgement, either, but questioning of elders is explicitly prohibited.

Even a group with "perfect doctrine" can be a cult if they conduct themselves as such.