On one hand, it is absolutely the responsibility of parents to raise their children.

But on the other hand if children using a service is reliably and consistently resulting in negative outcomes for the children and their families, it seems reasonable to suggest something should be done. And that something could be 'companies don't provide chat bots that allude to children murdering their parents'.

Taking a legally or logically 'correct' position on something when it's actively harming people isn't really a morally defensible position in my mind.