That's not really how Ethics works. Hanging homosexuals is ethically wrong even if it fit popular support. Slavery is ethically wrong regardless of what people

That's not really how Ethics works. Hanging homosexuals is ethically wrong even if it fit popular support. Slavery is ethically wrong regardless of what people vote for. How we judge past decisions is more complex then only the ethics, including knowledge, context, norms, etc. but the ethics can be pretty clear (can be because they can also not be clear, but they can certainly be clear.)