If morality is subjective, then moral radicalism is possible, where a person can create a moral framework in which many cruel and heinous actions are considered good. For example, killing, torture, rape, and many other cruel actions can be considered good by another person, and you can’t say it is invalid. Because morality is subjective and because it is his moral framework, he will prioritize his moral framework rather than others’ moral frameworks, leading to moral radicalism if morality is subjective.
But even if objective morality exists, the same scenario can happen. People have a misconception that in objective morality, the things we consider bad, for example, killing, torture, rape, and many other heinous actions will be bad. But this doesn’t have to be the case, because objective morality means morality that is mind-independent; it exists as a mind-independent thing. So, if that’s the case, then it is possible to have a scenario where, in objective morality, slavery, killing, torture, and many other cruel things are good, and the things we consider good like helping each other, being kind, and many other virtuous actions are bad. This scenario is possible even under objective morality. In the end, it is a mind-independent morality, so there are no guarantees that it will align with our general moral values.
So, both can lead to moral radicalism where cruel and heinous things are considered good. If that’s the case, then does morality even matter? Should we even care about being good or bad when they can be used for radical purposes? And if morality doesn’t matter, then what should we do? Should we live without action-guarding values, where any action is permitted, or should we have action-guarding values? If yes, what should those action-guarding values be?