it sounds like what you are interested in is negotiating mutually beneficial bargains with people, then, or manipulating public opinion in your favor, by applying the currently fashionable ethical norms (or at least appearing to do so) and attempting to shape them to your liking
in the former case, you don't seem to be offering to make any concessions (and in any case, how could you, in a public forum like this), and in the latter case, it seems like it would be in people's best interests to close their ears to you except when your arguments are factual (as opposed to normative); and possibly even then, if their interests are likely to run counter to yours, because selective reporting of facts can manipulate people to act against their own interests just as effectively as outright lies
that's what i mean by 'there would be no point in discussing ethical issues at all if moral relativism were correct'. there is certainly a point in negotiating agreements, or even evaluating who is likely to fulfill their negotiated commitments, but that isn't the same thing as discussing questions of ethics
attempting to return to the substantive questions, perhaps we would do well to promote pseudonymous and even anonymous online interaction (especially for media likely to be used by edgy and troubled teenagers) and not grant governments the ability to eliminate facts from the historical record piecemeal, like beria editing stalin's opponents out of photos