While I understand applying legal constraints according to jurisdiction, why is it auto-accepted that some party (who?) can determine ethical concerns? On what basis?

There are such things as different religions, philosophies - these often have different ethical systems.

Who are the folk writing ai ethics?

It's it ok to disagree with other people's (or corporate, or governmental) ethics?

In reply to my own comment, the answer of course should be that ai has no ethical constraints. It should probably have no legal constraints either.

This is because the human behind the prompt is responsible for their actions.

Ai is a tool. A murderer cannot blame his knife for the murder.