Political coverage is never more trivial or evanescent than during an election. Where we might hope for enlightenment about the issues on which we will vote, we find gossip about the habits and style of political leaders, an obsession with statistically meaningless shifts in opinion polls and empty speculation about outcomes. (All this is now compounded by the birth of a royal baby, which means that our heads must simultaneously be dunked in a vat of sycophantic slobber.) Anyone would think that the media didn’t want us to understand the real choices confronting us.

While analysis of the issues dividing the political parties is often weak, coverage of those they have collectively overlooked is almost nonexistent. The Conservatives, Labour, the Liberal Democrats and even the SNP might claim to be at each other’s throats, but they have often reached consensus about which issues are worthy of debate. This article will list a few of the omissions.

The first is so obvious that it should feature in every political discussion: the corrupt and broken system under which we will vote. The argument I’ve heard Labour activists use – “vote for us because it’s the best we can hope for under first-past-the-post” – would carry more weight if Labour had any plans to change the system.

Where are the furious arguments about the UK’s unreformed political funding that allows billionaires and corporations to buy the politics they want? Where is the debate about the use and abuse of royal prerogative by successive prime ministers? Where is there even a mention of the democratic black hole at the heart of Britain, into which hopes for financial and fiscal reform are sucked: the Corporation of the City of London, whose illegitimate powers pre-date the Magna Carta?

Here’s a fact with which politicians should be assailed every day: the poor in this country pay more tax than the rich. If you didn’t know this – and most people don’t – it’s because you’ve been trained not to know it through relentless efforts by the corporate media. It distracts us by fixating on income tax, one of the few sources of revenue that’s unequivocally progressive. But this accounts for just 27% of total taxation. Overall, the richest tenth pay 35% of their income in tax, while the poorest tenth pay 43%, largely because of the regressive nature of VAT and council tax. The Equality Trust found that 96% of respondents to its survey would like a more progressive system. Yet where is the major party mobilising this desire, or even explaining the current injustice?

Where are the arguments about the UK’s political funding that allows corporations to buy the politics they want?

A comprehensive failure to tax land and property is a policy shared by the three major English parties, mansion tax notwithstanding. None of them seems to mind that this failure helps to replace the entrepreneurial society they claim to support with an economy based on rent and patrimonial capital. None of them seems to mind that their elaborate fiscal ringfencing of land and buildings clashes with their professed belief that capital should be used productively.

Nor will any of them mount an effective challenge to kleptoremuneration: executives siphoning off wealth that they had no role in creating. None seek to modify a limited liability regime so generous that it allowed the multimillionaire authors of the financial crisis – such as Fred Goodwin and Matt Ridley – to walk away from the pain they helped to inflict without forfeiting a penny.

Even these issues are trivial by comparison to the unacknowledged cloud that hangs over our politics: the impossibility of infinite growth on a finite planet. All major parties and media outlets are committed to never-ending economic growth, and use GDP as the primary measure of human progress. Even to question this is to place yourself outside the frame of rational political debate.

To service this impossible dream we must work relentlessly, often in jobs that deliver no social utility and cause great harm. Who in politics is brave enough to propose that we work less and enjoy life more? Who will challenge working conditions characterised by ridiculous quotas and impossible demands, or reform a social security regime more draconian and intrusive than day-release from prison? Who is prepared to wonder aloud what all this striving and punishment is for?

And how about some acknowledgment of the epidemic of loneliness, or the shocking rise in conditions such as self-harm, eating disorders, depression, performance anxiety and social phobia? Evidently, these are not fit and proper subjects for political discourse, which creates the impression that those who suffer them are not fit and proper electors.

How about some arguments over the loss of public space? Or a debate about what’s happening to children, confined as never before within four walls, both at school and at home? How about some recognition of the radical changes in transport demand that are likely, in the age of peak car and peak plane, to render redundant the new roads and airports to which all the large parties are committed? Forget it.

A narrow public discourse, dominated by the corporate media and the BBC, ignores or stifles new ideas

The national and global collapse of biodiversity, the horrifying rate of soil loss, the conflict between aspirations to minimise climate change and maximise the production of fossil fuels: none of these are put before voters as an issue of significant difference. All major parties tacitly agree to carry on as before.

Politicians will not break these silences voluntarily. They are enforced by a narrow and retentive public discourse, dominated by the corporate media and the BBC, which ignores or stifles new ideas, grovels to the elite and ostracises the excluded, keeping this nation in a state of arrested development.

After this election, we need to think again; to find new means of pushing neglected issues on to the political agenda. We might try to discover why social media has so far mostly failed to fulfil its democratising promise. We might seek new ways of building political communities, using models as diverse as Spain’s Podemos and evangelical Christianity. We might experiment with some of the Latin American techniques that have helped to transform politics from the bottom up. However we do it, we should never again permit democracy to be reduced to so narrow a choice.

• Twitter: @georgemonbiot. A fully referenced version of this article can be found at Monbiot.com

• Jonathan Freedland is hosting Guardian Live: Election results special, on Friday 8 May at 6pm in Kings Place, London. Polly Toynbee is a panellist. For full details and to book tickets, see here