That's the trouble with public service broadcasters, they are not immune from political interference.
Jeremy Corbyn got it right, rather than make the controller a political position make them accountable to a independent body. This should go some way to repairing the BBC's bias problem.
It won't happen though they are too good a propaganda outfit. Who for? The establishment. Whichever party is in power. So, you want to change the BBC? You need to change government.
And for those that advocate abolition, at least with the current system, you have one lever of power. Good luck in influencing Rupert Murdoch to sway his reporting.