Reality is Objective/Subjective And So Is Ethics?
If one can be objective, then there's a basis for saying that the opposite is objective also. Epistemically, neither may be known, and each has the same qualities to the individual, e.g. they're felt, or experienced.
Although it will never be directly experienced objective reality can't be countermanded and should be contended with in a means that doesn't violate its apparent nature. Morality doesn't impose upon us in this manner. Regardless of what morality you take after you will do violate its apparent nature.
Purely Human Generated
While neither is truly verified conclusively, morality would appear to be a strictly human idea whereas reality would seem to be a condition of physicality. This argument, at least for me leads me to believe that whereas some objective reality should exist that no objective morality necessarily does.
Both objectivity and ethicality (the criteria for morality) are philosophical fictions, like 'zero', or infinity, or perfection. They do not exist in any manner that we can truly ascertain. However, they operate for as ideals through that we understand and perceive the actuality of existence as we experience it.
Perfection We Strive Towards
So as functional ideals, both objectivity and ethicality "exist" and are "true". However as phenomena in and of themselves, and aside from us, they do not, thus far as we've ever been able to ascertain.
Suppose the statement "humans ought to not murder" was an objectively true statement. Despite the fact that we can conceive it as being objectively true, it doesn't suggest it can't be countermanded as you say. It's totally different from the statement "humans cannot murder" which, if objectively true, would imply an inability for humans to murder.
Murder is unacceptable to me as a result of that fact that I possess sufficient sympathy that in understanding that I would not wish to be dead nor to have my loved ones murdered that I would be harming somebody and all their adored ones by committing murder. Maybe morality is subject to sympathy. It's also a part of our shared experience and groups of individuals tend to trust local morality to an extent, which makes morality subject also to geography.
