'Bad for the experiment' and ethical are orthogonal. There's an enormous body of work on the ethics of social science research, and an awful history of the consequences of such research that wasn't guided by consent and other ethical considerations.
If you're genuinely interested in answering those (likely rhetorical) questions. Check out work on the ethical dimensions of deception and covert research, especially relating to online research. e.g.: https://ec.europa.eu/info/funding-tenders/opportunities/docs...
I see it from the perspective of the guy doing the "experiment", why should HE be ethical? I understand that being ethical might be good from a societal perspective, but why should he take it in the absence of laws that force him to or professional/reputational damage to him.
So then you do understand why he should be ethical: being an unethical person is a bad thing.
> why should he take it in the absence of laws that force him to or professional/reputational damage to him.
If the only reason that you behave ethically is because you will suffer consequences if you don't, then you are not ethical. I'd hope that such a person would have problems looking themselves in the mirror, but I know better.
For "real science", like from within a university, it makes sense, as you must placate (beat) the ethics commission (they can generally be considered adversarial to research).
For this private kind of fun science, there is no need for ethics, unless one commits a crime or fears loss of personal reputation.
- High chance of being outright rejected.
- potentially makes responses to your AI responses less natural