Those who edit/write for newspapers & are involved in broadcasting have particular views due to their shared education, class, age.
Remember Ralph Miliband?
They write from a particular perspective unconscious of bias.
BBC and others are part of the establishment that accept the dominant ideology of the state.
Consider the current economic climate, the dominant ideology of society says that debt is bad and should be paid off at all costs and the main media outlets don’t challenge this. There are many other ways of tackling an economic crisis, these aren’t considered.