If you think that the BBC, home of Nigel Farage, is left of centre then you’re unlikely to ever agree with my central point. There have been numerous independent studies that have concluded its bias is to the right (more airtime to Tories, tendancy to quote rightwing thinktanks as authorities without ever referencing their conflicts of interests, favouring the opinions of big-business and City voices over those of the left etc).
The Independent’s editorial before the 2015 election was calling for a repeat of the Cameron-led coalition - hardly a cesspool of anything leftwing. The Sun is the mouthpiece of Murdoch and a close relative of Fox News so I have no idea how it could be categorised as 'changeable’? The Guardian is the only one you mention that has leftwing voices, but they give space to Tories too; I’d say they’re Liberal overall (Polly Toynbee is probably their leading political voice and I’d say she’s just left of centre).
As I've said, my point wasn't about Corbyn but about politicians not being given the space to advocate leftwing policies. Which of the media outlets you mentioned actively push for nationalising utilities, for example? The Guardian is the only one that might occasionally allow a journalist or two to entertain the idea.
I'm trying to get away from Corbyn because he isn't central to my point, and again, I'm not a supporter of his and I abhor antisemitism. But you seem to be suggesting that the further left you go the more antisemitic you get, which is frankly nonsense - apologies if that wasn't what you were trying to say.
Your final comment about Marxism being responsible for 100m deaths suggests maybe you’re confused about what Marxism actually is. I think this is symptomatic of my point about leftwing ideas not being openly discussed. Marxism is not the same as Communism, which is not the same as Stalinism. Marx is widely regarded to have offered the best critique of Capitalism to this day. Stalinism was of course undeniably Left, but the death tolls of Stalinism should not be attributed to Leftwing thought in general; similar arguments could, in that case, produce similar figures for rightwing thought (for instance it can and has been argued that slavery was Capitalism in its purest form).
It's clear your politics are far to the right of mine, so we're unlikely to agree, which of course is fine. But I hope at least we can both agree that the position of the centre ground can be thought of as subjective!