I would compare the BBC to PBS a quasi-government operation that gets US taxpayer money, not the private MSNBC or Fox. BBC gets public funding. Can you imagine a public entity like PBS politicking the US government? That would be unheard of. It may be illegal. Of course, PBS does do that by the type of shows it produces, mostly liberal. But then, it just claims it's presenting different ideas. But they could not take a public position like the BBC can get away with.
The "quasi-government" news agencies (although publicly supported is more accurate) are the only ones I can stand listening to, BBC, CBC, PBS, TVO (in Ontario). I cannot take seriously any of the private networks, consisting mostly of smiling blondes with really large incisors. I am mostly referring to Canadian and American private networks here, I don't have much experience with any others.
What bias the semi-public networks exhibit is easily discounted for, I find, whereas with private networks it's not always easy to know what they're trying to really sell you, which is their main function, imo. In the case of Canada's CBC, governments of every political stripe have routinely bashed the CBC for being biased. The fact that all politicians hate a news source is encouraging to me, as it indicates they may be doing their job. Unlike some (Trump, for instance), I don't think that the press is the government's marketing department.
To me, the susceptibility of a private outlet serving as a propaganda tool is much larger than that of a publicly supported network. Libertarians and Alan will of course disagree but I am basing my opinion on a lifetime of observation, not ideology. It seems like a contradiction, that a publicly funded network is more objective, but seeming contradictions often indicate incomplete understanding of what is really going on.