Religious indifferentism, precisely defined by the Church, is “the identification of all religions, based on a purely formal and symbolic concept of religion, which is always ready to regard the content of religion merely as a mutable manifestation and never as an authentic content.” Das neue Volk Gottes, Joseph Ratzinger, Düsseldorf: Patmos, 1969, 350.
In other words, indifferentism, which claims all religions are basically the same, means that all religions are pure myth, that they have no real truth content. That their claims of truth are really false.
Nietzsche is representative of the post-Kant deconstructionists who say that the honest and true motivation, therefore, is to be rid of what they hold is the sham of all religion and pursue the true and do the good altruistically, just because it is right. There is a double problem with this proposal of modernity: how to ultimately know what is true and right (who decides what the absolute standards are?) and what do you do with the fact of evil (the fact that man is free to choose "evil", however you define it)?
The relativists say that men can be good without God but they cannot tell us what is good or what is evil without reference to him and they do not have the sufficient motive for doing good and rejecting evil which is love, personal responsibility, with the ultimate Person, Who, in the end, rewards the good and punishes the evildoer, i.e. makes all things right. Without that relationality of the creature (man) before his Creator (God) there is ultimately no responsibility, when the world does not give you any hope of justice. Where does one turn in the face of great evil to stand firm on what is true and right? Martyrdom! God! Man relies on God! Man will give his life for the truth which is the source of the meaning of his existence. It was this truth which ultimately prevailed against the false utopia presented by the atheist Communism of the Soviet regime. All of the ghettos of America are formed upon the same systemic apathy produced ultimately by the denial of God and of His morality, the only true way to live as men.
"There cannot be a free society among citizens who habitually lie, who malinger, who cheat, who do not meet their responsibilities, who cannot be counted on, who shirk difficulties, who flout the law-or who prefer to live as serfs or slaves, content in their dependency, so long as they are fed and entertained..."
"...Liberty is not the freedom to do what you wish; it is the freedom to do what you ought. Human beings are the only creatures on earth that do not blindly obey the laws of their nature, by instinct, but are free to choose to obey them with a loving will. Only humans enjoy the liberty to do-or not to do-what we ought to do.
"It is this second kind of liberty—critical, adult liberty—that lies at the living core of the free society. It is the liberty of self-command, a mastery over one’s own passions, bigotry, ignorance, and self-deceit. It is the liberty of self-government in one’s own personal life. For how, James Madison once asked, can a people incapable of self-government in private life prove capable of it in public? If they cannot practice self-government over their private passions, how will they practice it over the institutions of the Republic?" Michael Novak Templeton Prize Address, 1994
P.S. Carlo Invernizzi Accetti in his book Relativism and Religion, (2015, 96-97) equivocates indifferentism and apathy in making his claim that moral "apathy" does not result from secular humanism, but that secular humanism does in fact have standards of conduct, viz. that each person must decide which type of conduct is God and which is the devil for him. That is what he calls democratic responsibility! Each person must take the responsibility to decide for himself what is representative of God and what of the devil. Again, the obvious problem is a complete denial of the reality of evil and man's capacity to do evil, real evil. Authors like Accetti, in line with Karl Marx himself, seem to live in a bubble where there is no sexual perversion, no abortion, no otherwise cold-blooded murder, no infidelity, no malicious violence, no terrorism. They create a fictitious world which is not inhabitable by men, a veritable monster which steamrolls the individual person and his rights in the name of a fictitious "responsibility" to decide in a mythical ontological and moral vacuum. A tyranny of anarchy where every man must make everything up on his own, re-invent a world for himself. Meanwhile, they all move to the suburbs because the urban centers of American have been rendered uninhabitable by their form of "responsibility" to decide what is right. NO! Peaceful worlds need laws, laws which apply to all men. Commandments of God, eternal truths!
The fact is that the denial of religious truth is a denial of God and therefore of absolute truth. And if there is no supra-temporal source and goal of human knowing how can you speak, ultimately, of right and wrong? Any serious conversation about right and wrong must have a universal breadth, i.e. over and above all individuals. Deny that, then anything goes: moral apathy.