Back in the days when incorrect beliefs about the trinity could get you into trouble, it became heresy to doubt that Jesus was god. Shortly thereafter some people stopped believing he was man, which in due course also became heresy. Much drama ensued on the question of whether Christ was cosubstantial with god, or consubstantial with god, and whether the holy ghost proceeded from Christ, or God, or both, and whether God was three or one or both.

Discussions of racism are apt to develop a similar character.

However, in the historical discussions of the Trinity, the opposing sides at least made it clear what exact beliefs they considered as orthodox and which heretical, and spelled out the criteria for orthodox beliefs and their official justifications at length, always ready to elaborate still further if any details remained ambiguous. (However arbitrary and illogical these official justifications may have been.)

In contrast, in the modern discussions of racism, sexism, and other ideological transgressions, it is never spelled out explicitly and clearly what exact beliefs one is supposed to profess to remain orthodox. Rather, there exists a pretense that there is a certain set of beliefs that will be accepted by all people who are not malevolent or delusional -- and if you ask for a precise and clear statement of what exactly these beliefs are (and let alone how they are justified), this is by itself considered as strong evidence of ideological transgression, since only a malcontent would ask so many annoying questions about things that are supposed to be plainly obvious to sane and honest people.

A clear and explicit list of official doctrine that it is forbidden to question, such as the those pronounced by various parties in historical trinitarian disputes, is at least honest and upfront in what it demands. What we see today however is the utterly mendacious and delusional insistence that the official doctrine is a product of pure rationality and free thinking that can be denied only out of insanity or malicious dishonesty.