Would his blood be on the hands of the researchers who trained that model?
If we were facing a reality in which these chat bots were being sold for $10 in the App Store, then running on end-user devices and no longer under the control of the distributors, but we still had an issue with loads of them prompting users into suicide, violence, or misleading them into preparing noxious mixtures of cleaning supplies, then we could have a discussion about exactly what extreme packaging requirements ought to be in place for distribution to be considered responsible. As is, distributed on-device models are the purview of researchers and hobbyists and don't seem to be doing any harm at all.
Or, I mean, just banning sale on the basis that they're unsafe devices and unfit for purpose. Like, you can't sell, say, a gas boiler that is known to, due to a design flaw, leak CO into the room; sticking a "this will probably kill you" warning on it is not going to be sufficient.