On a simple textbook view of technological development, old technologies are superseded by new ones. The pen gives way to the typewriter, which is rendered obsolete by the personal computer. The spear gives way to the sword, which moves aside for the manual gun, which is finally superseded by automatic weapons. It’s a powerful story, and it is shaping how a lot of people understand the future of urban transport. Once, we humans relied exclusively on our feet to get us around. Then we domesticated the horse. Next came the cart, followed much later by the train and cars, lorries and buses. Older automotive technologies then gave way rapidly to more sophisticated ones – manual steering to power steering, manual ignition to electric, and so on.

Seen in this way, the future of urban transport looks fairly clear, at least in outline. New digital technology – “on demand” services, sharing platforms and, above all, self-driving vehicles – will revolutionise the way we move around our cities. The demise of the black cabs is inevitable and services like Uber and Lyft are the future.

Private cars will give way to car clubs; cars driven by humans to cars that drive themselves. It’s a story that works very well, of course, for those developing the new tech-enabled services, and these people are among the most vociferous and influential in telling it. How could anyone but a Neanderthal troglodyte side against these new, progressive technologies?

I want to suggest that it’s rather more complicated. Not only is urban travel unlikely to develop along the iron lines the techies envision, but, if it did, we could all be losers.

Note, first, that as things stand, old 20th-century technologies seem to be lingering on beside new 21st-century ones rather than giving way to them. The problem is that there is not always room on our streets for both.

Much of our policy framework still favours the private car. I can rent a car-parking space outside my house for £15 a month, which, given the price of buying or renting a home in London, is absurdly cheap. I am charged no more to drive along the Euston Road at rush hour, where I am taking up valuable space, than to drive along an empty motorway in the middle of the night, where space is abundant. So although car ownership is declining, it is not declining fast.

At the same time, new technologies are bringing new pressures. We have private cars; old-fashioned and increasingly empty buses; black cabs; Amazon-style delivery vans; and Uber-type cab services, all jostling for space. The result is growing jams and delays. Congestion on London Roads grew by 12 per cent a year between 2012 and 2015. ⁸ Our regulatory framework feels badly designed, and desperately needs updating.

A more sophisticated version of the technological progress story is needed to account for this level of complication. The transition from one technology to another has always been messy. Government has often had to take a role. The horse and cart trade no doubt lobbied hard against the internal combustion engine, just as the black cab trade is lobbying hard against Uber, Lyft and co. Unions representing HGV drivers will protest against the self-drive newcomers, but will eventually have to succumb to the march of progress.

Even this more sophisticated, story doesn’t really account for what is going on – because what we have is not simply two tech ages jostling for space, but three, or perhaps four. Yes, horsepower seems to have gone forever. But cycles, once marginalised by the car, are making a big comeback. Equally, people have always continued to walk in cities, and would be happy to walk more given the right conditions.

Images of future workspaces promoted by computer companies typically show pristine desks empty of anything but a screen and keyboard.

Our real-life desks are rather different, with computers jostling for space with notebooks, piles of paper and printed books and reports.

Similarly, images of a future city put out by AV companies offer us roads are full of nothing but driverless cars. Reality is likely to be rather different. Yet, for all their persistence and importance, old ways of getting around have an uncertain place in tech visions of the future.

In a 2016  TED talk watched more than 2m times, Wannis Wajab, a scientist working for UBS, heralded a new future for our cities in which driverless cars will flow freely down roads and streets without ever having to stop at junctions. ⁹ Wajab makes use of an old metaphor: the city as human body, with roads as veins. Right now, he says, our urban vascular system is clogged up, as drivers slow down or stop at junctions. But autonomous vehicles will be able to flow freely across junctions. Traffic lanes, traffic lights and “give way” signs will be things of the past.

It’s an alluring vision, but it is striking that Wajab’s city roads and streets are populated by nothing but driverless cars – no pedestrians, no cyclists and no cars with drivers. The traffic lights have gone, but so have the pedestrian crossings and the cycle lanes. And it’s pretty obvious, once you think about it, that you can only achieve the free flow of autonomous vehicles that Wajab seeks by banning all other users from self-drive routes. Wajab’s vision is strikingly similar to the familiar old 20th-century Modernist visions of cities dominated by urban motorways.

Another, perhaps better, way of thinking about the future is to reform policy not to deliver a tech revolution, but to put walking and cycling centre stage, with vehicular technologies fitting in around them. I am not saying that this is the right way, only that it’s an option – and one that would deliver us a very different, probably more sustainable and probably more healthy future than the one presented as “enlightened” by the techno-progressives.

There is another weakness inherent in techno-progressive visions of urban mobility, which is well illustrated by Wajab’s talk. It never seems to have occurred to him that roads and streets have not only a transport but also a place role. People use streets for exercise, to play and to socialise, as well as to move around.

But the place function is often in tension with the movement one. Roads given over to the frictionless flow of autonomous vehicles are unlikely to be enjoyable places to sit and have a coffee or walk the dog. Any pedestrian activity that threatened to impede the free flow of traffic – children playing ball games, or teens on bikes – would need to be strictly constrained. Yet a city of wide, busy, tree-lined pavements and quiet cycle-filled roads provides another vision of the future – surely one at least as attractive as streets dominated by autonomous vehicles?

All this might seem obvious when you think about it. But the simple technological story is a powerful one. We are easily drawn to it. We need to remind ourselves of its limitations.

Ben Rogers