But I'm not sure that the existence of such an element means that our ethical systems are utterly devoid of objectivity. What if objectivity is a matter of degree?

Here's an interesting example of what I mean. Philosopher David Wong has listed five claims that philosophers may be making when they refer to ethics as objective. I'm going to read directly from the very first page of his book Moral Relativity.

1. Moral statements have truth values;
2. There are good and bad arguments for the moral positions people take;
3. Nonmoral facts (states of affairs that obtain in the world and that can be described without use of moral terms such as 'ought,' 'good,' and 'right') are relevant to the assessment of the truth value of moral statements;
4. There are moral facts (that may or may not be claimed to be reducible in some way to nonmoral facts);
5. When two moral statements conflict as recommendations to action, only one statement can be true;
6. There is a single true morality.

I think Wong's list is plausible, and I think he is right that our ethical systems can have some of these elements of objectivity even if they do not have them all. Some theories of ethical relativism are compatible with this possibility too. Wong believes that his relativistic theory can accept claims one through four as true.

As a result, it may be a mistake to classify ethical systems as objective or subjective. Perhaps there are elements of objectivity even in relativistic theories of ethics even if they are not entirely objective.