[impendia]

If the government's guidance isn't to be at least mostly trusted, then I'm not sure the government should be offering guidance at all. (Which is perhaps a sensible position in itself.)

In other words, if I learn enough about nutrition to be able to critically evaluate the government's guidance, then is that guidance adding any additional signal? At that point, I should just rely on my sources about nutrition.

I've never been one to rely on official guidance blindly. For example I don't show up to the airport two hours early, and cheerfully laugh at advice that I should. But I'd like to believe that this guidance is better than total nonsense.