How would people have read that math in the diamond?! And how would math transmit moral values? I feel like this leaves the realm of mathematics, lol. You complain about the best way to do things in this world (despite the time and alterations) but provide no alternative. If God wanted us to be perfect, he would've made us without free will, just automatons following moral law, but he gave us free will and wants us to be good, as there's no perfection in this world. The direction and base idea of things like the TC are undeniable and easily understood, but if one wants to rationalize and deform the words therein they can, one can be as silly as possible if one wants to. If you want to rationalize murder even though they told you not to kill, or rationalize cheating even though they told you not to lust over women you're not married to, well, that's on you (didn't a Brit king create a whole religion just to cheat?). And God will remind you of what you did and deal with you accordingly, of course. But no one can, in good faith, both say they believe in the TC, for example, and God's judgment and actively go against it. You can lie, to yourself and others, about it but you can't do that in good faith. Who would rather taste Hell than not?
And how are people not being "real people" a thing? Where does God say some people are people and others aren't? Why is murdering an innocent adult okay but not an innocent child? What? Which divine mandate? I'm only speaking for monotheism, best encapsulated in the Qur'an, but again, I don't see "God chose me so I can be immoral" in the Mosaic laws, in Ecclesiastes or the message of Jesus. And the Qur'an is pretty detailed when it comes to war and how it's even better to release prisoners (some societies take no prisoners but it's better not to kill in Islam and all of Abrahamic monotheism), even if they initiated the war. And all you've given me is examples of heresy, not belief. Come on, man. Of course these people exist, and maybe that was the spin they used to convince others but they fully knew what was up (or they also lied to themselves a bit and only partially knew what was up, which is why it's a good policy to be honest), that's why they had to spin it in the first place. You can't both believe, truly, that your soul is going to Hell for committing grave transgressions and also commit them, unless you're actually insane and want to be deservedly tortured for your own misdeeds forever. Most people are not crazy, though.