> Au contraire, subscribing to hard DCT is an active choice I made.

Catholic teaching (both traditional and contemporary) is that objective morality is inherent in the very nature of created things, and hence knowable in principle by anyone who knows those created things–even a convinced atheist. If by "hard DCT", you mean that good and evil are (in the general case) contained in the contingencies of God's free will as opposed to the necessity of God's own nature (theological voluntarism) – such that God could have chosen to command murder instead of prohibiting it, in which case it would be good rather than evil; and that right and wrong are unknowable except through special divine revelation (e.g. the Bible) – then Catholicism condemns that as heresy

Since you advocate taking away the religious freedom of atheists and non-Abrahamists (Hindus/Buddhists/Sikhs/Jains/Taoists/Shintoists/etc) – would you be okay if a Catholic theocracy persecuted you for your own belief in "hard DCT", given that according to Catholicism it is heretical?

Indeed, from a traditional Catholic perspective, hard DCT is a socially harmful heresy – by reducing right and wrong to God's whims, it encourages aberrant sects which justify all manner of evils as God's prophetic command; by falsely claiming that non-believers are incapable of knowing objective morality, it discourages them from seeking to know and understand and obey that morality, and gives them an excuse with which to evade their own moral responsibility. If any heresy is sufficiently socially harmful to justify its persecution, your own "hard DCT" is arguably among them.

I get the impression you are Muslim, or at least leaning in that direction. "Hard DCT" is the Asharite position, so you might call it the mainstream traditional Sunni view. Catholicism's view on this topic has been influenced by Islam, since Ibn Rushd (Averroes) was a big influence on mediaeval Latin Catholic philosophy (including Aquinas), and through that on Catholic theology too. Something close to the Asharite position occurred among Catholics as well - William of Ockham and the nominalists, most notably – but Catholicism ended up decisively rejecting that approach. It still has some advocates among Protestant philosophers (most notably nowadays, Robert Merrihew Adams)–but the Catholicism of recent centuries has rather decisively ruled it out.

By contrast, in Islam, Ibn Rushd's viewpoint was adopted by the Mu'tazilites, but opposed by the Asharites, and the later generally won out over the former; unlike Ibn Rushd, al-Ash'ari and his followers were ignored by Latin Catholic Europe. The Mu'tazilites largely died out, and their theology was not accepted as orthodox in Sunni Islam. However, Māturīdism, which can be viewed as somewhat of a compromise position between the Mu'tazilites and the Asharite views, is generally accepted as an orthodox Sunni theological school–and it agrees with Ibn Rushd, the Mu'tazilites, and Catholicism, in rejecting hard DCT.

My impression is that Asharite theology is more popular than Maturidite theology in contemporary Sunni Islam; while there is no necessary correspondence between schools of Islamic law (madhhabs) and schools of Islamic theology (aqidah), in practice Hanafis tend to be Maturidite while the followers of the other schools of fiqh tend to be Asharite or Atharite instead, and Hanafis are only about a third of contemporary Sunni Islam. Twelver Shi'a theology also rejects the "hard DCT" viewpoint of the Asharites; a basic principle of Twelver Shi'a theology is that right and wrong are an inseparable part of the divine essence, not just what God happened to choose to make right and wrong. I'm not entirely sure what the Atharite position is, if they have one; but if we take Ibn Taymiyyah as representative of Athari theology, he condemned the Asharite position that God could have chosen to make evil deeds good – which suggests that "hard DCT" is contrary to the Atharite position.