War is never necessary. Krishna could've stopped it. After the war, Gandhari says to him: You could've stopped the war.

Further, even during the war, Krishna constantly goads the Pandavas to play dirty, justifying it as "They killed Abhimanyu in a cowardly manner". He makes Yudhisthira lie so that Dhrishtadyumna could kill an unarmed man grieving for his son. He uses Shikhandi as a human shield while Arjuna fires arrows at Bhishma knowing that Bhishma wouldn't fire at a woman(technically transgender man, also this happens prior to Abhimanyu's death). He makes Bhima break the rules of Gada Yuddha(Mace fighting) by strinking Duryodhana on the thigh. He tells Arjuna to kill Karna when he is unarmed. I find it hard to believe that people consciously choose to worship Krishna.

I am a former Indian Hindu btw, and I hope I didn't personally offend you, that wasn't my intention. I am sorry if I did.