> There was a point where they told the public that masks don’t help.
Because that was a widespread belief among researchers at the time.
> recently one of their leaders said that “asymptotic transmission is rare” which is a deadly lie.
First, it wasn't a "lie," and using that hyperbolic language is not helpful. Second, there is still a lot of confusion within the scientific community about whether asymptomatic transmission actually is important. Studying transmission is really difficult. Further, the WHO official did not definitively state that asymptomatic transmission is rare. She made it clear that the whole question is very uncertain at the moment - because it is.
> incalculable damage is done by these mixed, inconsistent messages.
The message is mixed because the state of knowledge about a lot of aspects of this virus is uncertain or changing. It's impossible (and undesirable) to be 100% consistent when the state of knowledge changes.
What is actually damaging is that people are attacking the WHO and trying to destroy it, because it hasn't met the impossible standard (omniscience about a novel virus) that the critics are setting. The WHO has done a very difficult job fairly well, and is being most viciously attacked by precisely the country that has had one of the most incompetent responses to the outbreak.