Thank you for saying this. It takes the discussion in a different, but I think more useful, direction. Suffering is caused when you believe something that isn't true, and the rational idealists don't want to accept "it's natural for people to believe in lies", as you say. (There is a juicy irony here, which I will leave as an exercise for the reader.)
The key innovation we require, as a society, are better feedback mechanisms to correct inaccurate beliefs. This means more frequent, but smaller, pain in response to mistakes. To those who object, the alternative isn't no pain, but rather, the catastrophic pain of collapse. Society is really a collection of institutions, and somehow in all institutions, loyalty has usurped principle, and accountability fails because the accuser is shunned, hated, feared. So, institution by institution, we weaken.
The solution, for example in academia, is to shun (fire, blacklist, etc) those "researchers" who cheat, lie, and distort their findings. In the justice system, lawyers, police, and judges who break the rules should be punished more, not less, severely than the rest of us. Again, these are not changes born of malice, or a desire to see more suffering, but rather a price we must accept to maintain healthy institutions with high standards, and so, prevent societal collapse.
In some ways I think "cancel culture" is a reaction to this lack of accountability, as an attempt to replace it, to ape it, almost like a cargo cult. Of course, there are huge problems with this, not the least of which there is not an institution behind it, but rather just mob rule that answers to no-one, not even itself.