This point is nonsense. — Rank Amateur
I really wish you'd read it and remember it, though. That you and others won't is why I have to explain it tens, if not hundreds of times, and why I'll continue to have to do so.
I have given you all a challenge, show that relative morality is a better explanation than some degree of objective morality for the near universal moral judgments on some actions. — Rank Amateur
Here's a very simple reason why:
Under subjectivist morality, the only explanation that we need for near-universal moral judgments is that our bodies develop in similar ways--a notion that's quite uncontroversial for most things (otherwise medicine wouldn't work, we'd not be able to explain why almost everyone has ten fingers and ten toes, etc.).
Under objectivist morality, we need to both posit (1) that moral stances somehow occur independently of us,
and (2) that we perceive them, cognize them, etc. significantly similarly, which we'd still only solve by positing that our bodies develop in similar ways (due to genetics, environmental influences, etc., just as above).
So per Occam's razor, subjectivist morality is the simpler approach; it doesn't posit unnecessary (and frankly unsupportable) entities. Objectivist morality has to posit the same thing that subjectivist morality posits (bodies thinking things, expressing moral stances, etc.), and it would have to explain commonality on that end via the same approach (bodies developing similarly, with similar abilities, etc., due to genetics, common environmental factors, etc.); but it posits things additional to that, too. The only way it could avoid doing this is by attempting to take bodies out of the equation, but I don't know how you'd do that and still talk about people agreeing on moral stances, people behaving morally, etc.
By the way, I'm saying "subjective" above, not "relative," because we keep using "relative" in contexts where that's not really what we're saying (and I really mean "we" there--I've done this many times, too, in the guise of going with the flow of the thread). Relative ethics/morality is broader than subjectivist ethics/morality (and not even necessarily overlapping with it). Relativists can be objectivists. They can believe that something occurs independently of persons. They'd just say that the thing in question can differ due to differing relations. All of that can be independent of persons on a relativist view. It's subjectivists who say that the thing in question is dependent on persons. Also, subjectivists are usually relativists (as I am), but they wouldn't have to be. A subjectivist could say that something depends on persons, but that it's invariable as such, and thus not relative at all.
An easy way to remember that relativists can be objectivists is to think of physics. Special and general relativity in physics aren't conventionally positing subjective phenomena. They're conventionally seen as claims about objective reality--ways that objective reality is relativistic.