At least in the COVID context, they were worried that any nuance would confuse the public, so they simply gave the simplified, dumbed down version.
Of course it backfired a bit. I honestly don't know what's the optimal play for them, but it seems a bit revisionist to say that they assumed the public was capable of filling in the gaps...
But when policymakers say there's no evidence for ivermectin's ability to treat COVID, I don't fault them because I see their choice of words as being aligned with the truth. Therefore they are accurately communicating science and good policy.
As with all uses of language, we have to look at it on a case-by-case basis whether it's being weaponized wrongly or used appropriately. I will criticize it when it's used wrongly, and otherwise not criticize it.