At some point in a person's "training" as a rationalist, there comes a time when they are supposed to be ready to undertake controversial conversation topics without spontaneous combustion of their discussions.

I've found that people, in practice, tend to believe this point comes about five minutes after they've been introduced to the concept of rationality.

Empirically, I do think people who've put sufficient effort into debiasing are better at talking about value-loaded topics than those who haven't. But that doesn't do us much good as long as we lack accurate metrics of rationality (introspective or otherwise), effective ways of telling people that they probably haven't leveled up enough to participate productively in a given discussion, or sufficient native forbearance. "You seem to be mindkilled" is about all we've got, and that tends to be interpreted, often correctly, as a partisan attack.