I can tell you that the expression had been in existence for possibly fifty years before Macaulay is credited with it and that it was used in a very different world. For a start, most of the general population neither had the ability to read and nor did they have the franchise. The press itself was nowhere near as consolidated and the age of the pamphlet was still in swing.
Whilst news organisations grew and coagulated before becoming the proper mass media of the late nineteenth and twentieth centuries, the phrase has still stuck and has come to mean something of itself. The narrative that the fourth estate likes to tell itself is that is like a gatekeeper of information and that one of its roles is to hold governments to account. Even so, some news organisations are fully aware of the power they wield and like to use it, to herd public opinion to their own ends; often in the process completely making a mockery of their narrative to hold governments to account.
Given this, why bother caring about the news? What's the point? Alain De Botton quite rightly points out in his book "The News: A User's Manual" that if you just chose to ignore it, your life might be better; in which case it then becomes a value and benefit analysis exercise, as to whether or not you pay any attention to it at all.
If you didn't know about ISIS, the Ebola virus in west Africa, who the new President of Indonesia was, the details surrounding MH370, the war that sometimes is and isn't in the Ukraine, Taylor Swift's new album, or who was thinking of running in the primaries for the US Presidency in 2016, would your life actually be any worse for it? Do you even know about those things now; does it make a lick of difference to you?
There are of course all sorts of things that might take your interest such as some television show, history, learning a language or a musical instrument, doing a spot of gardening, bike riding, running, going to the gym, watching football on telly and yes even watching the news might all be adequate forms of entertainment. Is there really a difference in principle to yelling at the telly because some striker has missed an open goal from three yards, or that George RR Martin has decided to kill off someone else on Game of Thrones, or that Petr Brewin the MP for South Marshfield has made some stupid comment in the parliament that you disagree with? It could be argued 'no' very easily.
So why care about the news at all? Why bother? There are other things which are equally; if not more entertaining that you could pay attention to.
You might not like to think about this but as you sit in traffic and/or on a sweaty tube train, millions of people all over the world have all come to that same conclusion: the news in principle, doesn't matter. If this be the case, what are the effects of this? Collectively if lots of people make the same decisions, then those decisions coagulate to form culture and more importantly, policy for action.
If people choose not to care abut the news, they probably also don't care about things like politics or economics either. If people in principle don't care about these things, then collective apathy surrenders policy power to those that do. This unfortunately might mean that power to enact policy action is surrendered to the rich, the already powerful and the sometimes cruel. Power is often seen as an ends to itself by those who wish to wield it and arguably surrendered power, renders those who have chosen to surrender it through apathy, powerless.
When the institutions that people once fought for because they felt that they ought to have them, or the rules which govern people's working conditions are changed to suit the powerful, or governments choose to go to war for sometimes spurious ends, people who have surrendered power through apathy don't really have the ability of then undo what has been done.
The reason for caring about the news then, isn't because it is interesting, entertaining or fun but because it is necessary that society remains informed. The things that governments and to a lesser degree firms and corporations care about (or are forced to care about via legislation) are those things that the public cares about. If society paid active attention to the news, they might start caring about issues like educating their children, or conditions that people both in their nation and abroad have to work in, or what happens to people if they decide to flee their own country because of war and famine, or policies to do with transport, or the arts and cultural institutions, or issues of justice &c.
Although the news is itself not the best delivery method of information (because commercial news is driven by profit and state-run news is driven by other agendas), it still remains the best yet invented method of delivering information to society. When society is informed, or cares enough to bother to inform itself, the information that it has picked up in the news becomes vital in the ability to make decisions. Those decisions might start at the ballot box, or in the writing of letters to politicians, or in protest action, or perhaps most important of all in their wallets and pocket books.
Remember, collectively if lots of people make the same decisions, then those decisions coagulate to form culture and more importantly, policy for action. If people care about the news, then the decisions of selecting governments, telling those governments what they should care about, the decisions of what to purchase and the big questions of justice and ethics, become the things which are turned into policy and legislation.
I don't think that the press should be held up as the gatekeepers of information and I don't know to what degree or even what the heck is supposed to be meant by the term "the Fourth Estate". People can choose to not care about the news but collectively if enough people don't, then power is surrendered. I would also argue that choosing not to vote is also a deliberate effort to surrender power.
My question then is, is society happy to live with the consequences? Moreover, does it care?
¹"The gallery in which the reporters sit has become a fourth estate of the realm."- Thomas Macaulay, reviewing Hallam's Constitutional History in Edinburgh Review, Sep 1828.