Everyone is somewhat missing the point here that the California bar is making.

They don't care if you use an AI or a Llama spitting at a board of letters to assemble your case, you are responsible for what you submit to the court.

This is just a bad lawyer who probably didn't check their work in many other cases, and AI just enabled that bad behavior further.

The American Bar Association, as well as every state bar association, published guidance on GenAI usage at least a year ago. The existing legal and ethical responsibilities go beyond just being responsible for hallucinations. Client information privacy, accurately tracking time and billing only for time actually spent on the case, etc.

As time goes on, it becomes less and less defensible to see this stuff.

This. Lawyers can use AI tools. But an attorney is ultimately responsible for everything that goes out the door. So they had better check the output from their AI tool carefully. In most firms (at least most good ones) someone would check every citation that goes out the door, even if it was written by an experienced attorney, so it speaks volumes that someone would fail to check citations generated by an LLM.