Could England’s future be a left-leaning south facing off against a conservative north?

London is changing, and so is the south of England. Whether recent predictions of a lasting drop in the capital’s population and emptied-out office districts will come true is still unclear. But something has definitely been happening, for the best part of a year: thanks to Covid and its disruptions, a sizeable number of people are deciding to leave the city and head elsewhere, chasing space, greenery – and, in many cases, the company of like minds.

Former Londoners, it seems, have recently set up home as far afield as Devon and Cornwall. Estate agents report relocations to such commuter-belt towns as Broxbourne in Hertfordshire, Reigate in Surrey and Aylesbury in Buckinghamshire. At the same time, people seem to be pitching up in and around places associated with a liberal, remain-ish view of the world: Oxford, Brighton, Bath, the more affluent parts of Bristol. In Frome, the Somerset town where I have lived since 2009 and which is now a byword for a broadly Green political outlook and a trailblazing town council, you can hear the endless crashes and clunks of house renovations ordered by new arrivals from the Big Smoke.

All of this is accelerating a change that was starting to become clear before the pandemic: in many places once seen as conservative with both a big and small C, signs of a shift towards a different kind of politics. This is part of the explanation for recent English election results that suggested the mirror image of Tory successes in old Labour heartlands: Conservative losses in such counties as Surrey (where they shed 14 county council seats), Hertfordshire, Cambridgeshire and West Sussex; Labour’s win in the mayoral contest that spanned Bristol, Bath and South Gloucestershire; and a strong showing for Labour and the Lib Dems in Oxfordshire, where the one-time party of the working class finished first in the well-known proletarian hotbed of Chipping Norton. The same applies to wins for the Green party in East Sussex, Gloucestershire, Suffolk and Kent.

For people on the left, this is good news. In the suburbs, the fact that one aspect of the story centres on a long-term move into greater racial diversity should also be a cause for celebration. But as England enters a new age of political polarisation, those endless lifestyle articles about whichever places beyond the capital are now held to have the correct mixture of artisan cafes and organic food markets also suggest other social changes that are much narrower, and introverted: what some people call “clustering”.

More than ever before, the mobility enabled by affluence and the chance to work from home are allowing some people to put down roots alongside neighbours with similar – or, increasingly, identical – views and values, who live in much the same material circumstances. And after a year of lockdowns shutting us away in filter bubbles and tight social networks, what may be taking shape in parts of the shires and suburbs threatens something just as monocultural: a kind of economic and political uniformity that might be built on the politics of virtue, but can easily seem inward-looking and intolerant.

“London is a machine which sucks in young graduates and then later spits them out into the south east,” wrote one economics blogger recently. In plenty of places, any dreams of an educated hipster utopia are rather compromised by justified local resentments about gentrification and rocketing house prices. Old Tory southern strongholds starting to feel the presence of new, left-inclined people are still a long way from being piled high with sourdough loaves and rainbow flags. Nonetheless, what is happening looks set to deepen the sense of England as a whole being an ever-more imbalanced country. If you want a possible vision of the future, picture a liberal, university-educated middle class concentrated – by choice – in the affluent south, while a reactionary conservatism speaks for more deprived parts of the country, and the tensions that surfaced around Brexit burst forth again and again.

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In 2008, the American writer and journalist Bill Bishop published a very prescient book titled The Big Sort, sub-titled “why the clustering of like-minded America is tearing us apart”. He painted a picture of people settling into “extremely homogenous communities – not just by region and state, but by city and town”, and set out his anxieties about things that would later explode so spectacularly between 2016 and the beginning of this year. He wrote about “segregation by way of life: pockets of like-minded citizens that have become so ideologically inbred that we don’t know, can’t understand, and can barely conceive of ‘those people’ who live just a few miles away”.

As they stoke the so-called culture wars, the Conservatives are deliberately exacerbating comparable tensions. Meanwhile, Labour is led by people who do not know what to do in response. One thing, though, is clear: the danger of its recent public paroxysms about the post-industrial north and Midlands, and Keir Starmer’s clunky attempts to appeal to these areas’ supposed cultural conservatism is that they have emphasised our national divisions and suggested people have to choose a side. For a party that depends on somehow glueing very different elements of the electorate together, this is surely not the cleverest move.

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In parts of the country that are often sneered at, there is an England that feels more inclusive, egalitarian and increasingly diverse: the more successful parts of the new towns built between the 1950s and 1970s, and the starter-home developments that now ring towns and cities. Politicians on the left should sample these places’ atmospheres: at their best, they suggest something akin to the writer JB Priestley’s postwar glimpses of “an England without privilege … as near to a classless society as we have got yet”.

There is also, I think, a conversation to be had about the media. Certainly, if “public service broadcasting” is to mean anything, it should ditch the kind of output that plays up our divisions (think, for example, of the weekly bear-pit that was pre-pandemic Question Time, or the anger that pours forth from radio phone-ins), and rediscover the importance of a kind of social and political reporting that reminds people of how the other half – seen from both sides – actually lives.

The Big Sort warns of the perils of societies “dividing by economic prospects, by years of education … and by political persuasion”. It insists that in any functioning democracy, we all need to understand that there are lots of people “who aren’t just like you. They don’t live like you, they don’t have families like yours, and they don’t think like you. They may not live in your neighbourhood, but this is their country too.” Amid shifts and changes that are only just beginning, this is a truth we all need to swallow. If we do not, we risk a future that will be not just bleak, but politically impossible.

• John Harris is a Guardian columnist