If we really have passed ‘peak London’, what does that mean for Britain?

London feels like a city that might be in trouble. The usual tourist crowds are gone. New towers of offices and overpriced flats stand empty. Recently extended railway stations are deserted for much of the day. Hundreds of shops have not survived lockdown. Thanks to Brexit and the pandemic, 700,000 foreign-born residents may have left the city since 2019: almost one Londoner in 13.

Politically, London has also fallen on hard times. Many of the government’s priorities – restricting immigration, “levelling up”, culture wars against urban liberalism, Brexit itself – are either implicitly or explicitly against the interests and values of the capital. The likely winner of this week’s London mayoral election, the Labour incumbent Sadiq Khan, is already quite a lonely figure: he is one of his party’s few holders of high-profile office, yet with limited powers, such as overseeing public transport, which the Conservatives are constantly trying to weaken further.

Meanwhile, many of the voters whom the main parties most want are not in London – which is often seen by both parties and the media as an impotent Labour stronghold with little influence on the wider political battle – but in the Midlands and the north of England, as the attention paid to the Hartlepool byelection has demonstrated. Many of these non-metropolitan voters are resentful of London’s privilege, real and imagined, as any visiting journalist from the capital soon discovers. But after 30 relatively fat years, from the late 1980s to the late 2010s, London’s future is looking much less comfortable.

Plenty of non-Londoners will be delighted. No other 21st-century capital has so dominated a large European country – economically, culturally, administratively, demographically and psychologically. “In the United Kingdom, London increasingly overshadows everywhere else,” wrote the radical leftwing geographer Doreen Massey, a Mancunian who ended up working and living in the capital. “These are huge changes, but they are barely addressed by conventional politics.” She was writing in 2007, when dislike of London had yet to find an effective political vehicle.

Other commentators used to be more sanguine about the city’s dominance. In a lavish special report to coincide with the 2012 London Olympics, the Economist magazine celebrated the capital as “Europe’s only properly global city” and “a magnet for rich and poor” alike. In 2016, just before the Brexit vote, it was forecast that London’s population might reach 13 million by 2050, a rise of 4 million, itself far bigger than the entire population of any other British city. Despite the sluggish economies of many other parts of Britain – and to an extent because of them, as moving to London could offer a way out – by the 2010s the capital’s growth had begun to seem unstoppable.

Few are saying that now. Instead, there are regular articles about the obsolescence of central London in an era of home working and online shopping, and about the advantages of smaller cities and country living over the expensive, stressful capital. In March, the British architecture magazine Building Design asked: “Have we passed peak London?”

One answer is yes – for now. All old cities have peaks and troughs. Critics of London’s recent supremacy often ignore the fact that it was preceded by half a century of war damage, deindustrialisation, depopulation and neglect by central government. When I moved to London in 1994, well after it had supposedly been revived by Thatcherism, it was still a city of derelict docks and old trains that wheezed to unscheduled halts deep underground.

Another way to address the “peak London” question is to ask another one: what would a less privileged capital be like for the rest of the country, and for Londoners?

It might be a better neighbour to other British cities, tempting away less of their talent. When the postwar capital was at its least functional, in the 70s and early 80s, many people in pop music and television made careers elsewhere, for example at Manchester’s Granada TV and Factory records. British culture was richer as a result.

A less-dominant London might make England feel more united, and less like half a country with a huge city-state attached. And a less-favoured capital might narrow the north-south divide, if resources were redistributed not just from London but from the home counties – in many ways, the most privileged English region of all, with its elaborate transport links to the capital and its long hold over the Conservative party.

A more modest London could be an easier place for most Londoners to live in. The city gradually hardened during its boom years into ever wider rings of unaffordable, often cramped housing, surrounding a core increasingly given over to the rich and luxury shopping.

However, Londoners should not imagine that reining in their city will placate all its enemies. Like the EU, it will always be blamed for something by some English people. That’s partly because, deep down, London unsettles them, with its different version of Englishness: its frenetic rather than pastoral spaces, its constant flux of foreign people and ideas, and its frequent demonstrations that the left can flourish where English free-market capitalism is supposed to be at its strongest.

If Sadiq Khan wins, expect it to be widely seen as less important and interesting than events further north. But it will be a sign that the future doesn’t necessarily belong to the Conservatives. Even in its current, diminished state, London is too big for England in many ways. But without such a city, England may not be a country that non-Tories can easily live in.

• Andy Beckett is a Guardian columnist