The is mostly right. When your assumptions about reality are false, it is hard to make good decisions.
But there is more than that. Many of those in the “progressive” world view have no compunction about lying or cheating to advance their agenda. They see the Constitution, and oaths to uphold it as “quaint” or “outdated”. They see any restraint on their actions as illegitimate.
In my college days, virtually everyone who had any political view at all was either a liberal or an occasional self-declared Trotskyite or Communist.
They viewed any other thoughts (conservative, libertarian, anarchist, whatever) as an insult to the body politic.
Since they were on a mission to make the world perfect anyone who got in the way was quickly dismissed as either irrelevant or stupid.
Their self-esteem was totally tied up in their belief system.
They literally could not function in a world where their beliefs were not validated and supported.
Welcome to the press room!
And, needless to say, there was no tactic too devious for them. They were fighting for justice and to save the world!
Their other defining characteristic—every one of them—is that they were arrogant and often down-right nasty.
There is another aspect. To run a news organization that actually conducts its own investigations and sends reporters out to remote sites and writes its own material...is tedious and requires upper-level review of everything to assure compliance with whatever standards happen to be in effect. You need reporters and writers and editors and the stuff takes time to put out. To run a news service that simply sucks AP, Reuters stories off the wire, and even more insidiously, gets its talking points directly from the administration (in the case where the admin is what their designated subject matter is) costs pretty much nothing and can be staffed with eager interns or recent J-school grads.
It’s massively cheaper and since the copy just directly parrots what the admin wants you to say, there’s less need for compliance checking or veracity checking because hey, athe WaPo and the NYTimes and the Des Moines Register all say the same thing.