I've heard the extreme, Corbynist, far left accuse the BBC of being too right wing but rarely (if ever) from the centre left.You haven’t been paying attention then.
The hatred of the BBC is hilarious and nonsensical too. The left think it’s right wing, the right think it’s left wing. Neither side realise that maybe it’s their politics that are ridiculous rather than ‘unfairly reported on’
Pretty much all of the centre right believes it's too far left though - that imbalance should tell you all you need to know.
I've yet to hear any comments on the BBC from the extreme right.