Does this sentence mean that rather than calling him a liar, it is more effective for journalists to call him deluded or deceived by someone?
Journalists should be tough when powerful people say untrue things. When those statements first hit the headlines, “false” packs plenty of punch. Reporters should demand to know the reason for the false statements. In cases like Mr Flynn’s, with clear evidence, they can say “he lied”. In cases like that of Mr Trump and the murder rate, journalists should demand to know his sources, perhaps asking whether the president trusts conspiracy-theorist websites over his own FBI. It hardly spares Mr Trump to call him “deluded” rather than a liar. Finally, there is the possibility that the president simply has no regard for the truth at all, not even caring whether he’s right or wrong. In that case, the press lacks an easy term for this kind of falsehood. Many won’t print “bullshit”, one proposed suggestion.
A taxonomy of dishonesty, The Economist, February 18, 2017 http://www.economist.com/news/books-and-arts/21717019-and-why-lying-isnt-same-talking-nonsense-why-press-should-call-out-politicians