Because that thought's beyond ridiculous.
Picking a random story from the BBC front page, https://www.bbc.co.uk/news/uk-england-manchester-61002096 , what do you think is inaccurate about it? Do you think the MD has not resigned? That there have not been queues? That they have mistaken the names of people involved? That Manchester does not in fact exist and is a liberal conspiracy?
(The main problem with political news is disproportionate coverage, double standards of scandal, and the selection of who gets quoted - as well as a vast area of "op-ed" which is not technically news but is on the same websites.
As well as reporting on "future" or "possible" events, which by definition are difficult to be accurate about)
I intentionally didn't call "descriptions of what happened" as "facts", because that would sidetrack the discussion on how to determine what's true or not etc. Just force media to clearly separate "here's what our reporters saw" from "here's what they think it means"
The US operated censorship during WW2: https://en.wikipedia.org/wiki/Office_of_Censorship ; who knows what would operate during the war with Canada?
I'm not sure whether you're ignorant of the near-total state control of media in Russia and Belarus, but how do you expect them to get accurate news?