Almost 20 years since the unveiling of the Millennium Dome, which promised to transform the post-industrial wastes of the Greenwich Peninsula, the area has become a junkyard of half-baked ideas and botched plans. Emerging from the tube station, you are confronted with a cacophony of competing structures: the tilting concrete struts supporting a glass canopy swerve drunkenly towards a wall of fat towers clad in a chequerboard of bronze, champagne and metallic dog-turd brown.

To the right looms a bulbous sales-suite-cum-gallery, to the left the jazzy shed of Ravensbourne University, while all around lie assorted oddments of public art and curated happenings, from a huge, twisted steel spire to a surreal dinner party in the sky – a table suspended from a crane where you can eat dinner, strapped to a seat, for £200. Completing the panorama of pointless whimsy, the pylons of Boris Johnson’s costly cable car stretch across the Thames in the distance.

This souped-up graveyard of novelty trinkets is a fitting place to find London’s answer to the High Line, New York’s verdant park built on a former train track. Billed as “a layered network of recreation, culture and wellness” by Knight Dragon, the neighbourhood’s Hong Kong-based developer, the raised footpath will weave its way around the district in a 5km loop “stitching together diverse ecosystems”.

There have been many cynical attempts to emulate the High Line since it was found that proximity to an elevated green space can significantly raise property prices, but The Tide, a new walkway on the peninsula, is perhaps the most brazen of them all. While the Manhattan footpath transformed an abandoned route in 2009, with the unintended consequence of accelerating local gentrification, London’s version has seen the construction of an elaborate steel structure specifically to elevate the value of a steroidal development of luxury apartments. It is the marketeers’ flimsy sugarcoating of “placemaking” in its most unashamed form, a textbook combination of greenwashing and artwashing, as a decoy to distract from the low levels of affordable housing. But perhaps the most surprising thing is that the architects of the original High Line are behind it.

“We were a bit sceptical about getting involved at first,” says Ben Gilmartin, partner at Diller Scofidio + Renfro. “We were originally approached to do an apartment tower, but we weren’t in the business of designing commercial towers, so we proposed a public space masterplan instead.”

There was already a plan for a 5km running track around the site, but they brought a seductive sprinkle of DS+R fairy dust. Gilmartin describes their concept as akin to a “charm bracelet”, a multilayered route that would link together the cultural flotsam already scattered around the site, from Antony Gormley’s Quantum Cloud sculpture to Richard Wilson’s sliced-open ship. “The idea was that anything that came along could plug in,” he says. “We imagined it plugging into Ravensbourne, shooting up over the highway and plunging straight through the new shopping mall, as well as having an arm flying off into the new film studios.”

It was a similar concept to the City of London’s postwar Pedway plan, except that, rather than each piece being built incrementally by a sequence of developers, this would all be built by the benevolent Knight Dragon – a company with a track record of changing its plans. The film studio idea has since been axed and the grand £1bn centrepiece by Santiago Calatrava – intended to be a combination of tube and bus station, with bars, shops and entertainment venues, as well as offices, hotels and apartments – is already being rethought.

The first kilometre-long section of The Tide has just been unveiled and, so far, it doesn’t quite live up to its claims of being a useful connective route. It begins at the unholy nexus of Terry Farrell’s gaudily wrapped offices for Transport for London and the swirling eyeful of Ravensbourne University, the overwrought death rattle of Foreign Office Architects, completed shortly before they split up in 2010 and looking like a giant Connect 4 game dressed in dazzle camouflage. In between these two hulks stands The Tide’s first cluster of steel “trees”, rising at jaunty angles to support the pedestrian deck above, with real trees sprouting from their splayed tops.

“It’s basically trees with trees on top,” says Gilmartin, explaining how the steel trunks contain the drainage, power and irrigation, while a combination of birch and pine poke through the decking above. Bearing the trademark DS+R digital streamlining, they look like platforms from a computer game, bio-sci-fi stalks with more than a touch of Thomas Heatherwick styling – recalling the fungal supports of his ill-fated Garden Bridge, or the curvaceous concrete platforms of his Pier 55 park in New York, currently under construction in the Hudson River, despite a legal battle to stop it.

There are 28 steel stalks in all, manufactured by a boat-builder in Italy and shipped here up the river. They support a 250-metre long section of elevated walkway that weaves between a dense obstacle course of vents from the tube station below, terminating in a platform overlooking the Thames. Some of the vent shafts have been wrapped in colourful harlequin costumes by Morag Myerscough, while the biggest is encased in a building of its own, the Prism, designed by Neiheiser Argyros (who also co-designed The Tide) as a faceted mesh box containing a cafe, public loos and a big digital media screen, adding to the landscape of tortured geometries.

When you’re standing on the elevated deck, looking out over a jumbled vista of vents and service hatches, it’s difficult to work out quite how anyone thought this was a good idea. It has no purpose whatsoever, apart from providing a slightly different perspective on the surrounding carnage. A flight of raked steps suggests an area where performances might take place, while another section swoops down to form a protective bowl around a cafe terrace, but the point of being raised five-to-nine metres above the ground – over an area that is already pedestrianised – remains a mystery. After the short jaunt, you descend back to ground to join the remainder of the 1km route, which is simply the pre-existing Thames Path, repaved and adorned with some new benches and canopies.

Along the way are a number of seats fitted with “audio meditation portals”. Perhaps visitors might dwell here awhile, gaze out towards Damien Hirst’s enormous bronze sea sculptures and Yoko Ono’s forlorn Wish Trees, and meditate on how Knight Dragon acquired the land in 2012 at a knockdown price, after £225m of public money had been spent clearing the site, and soon set about reducing the agreed requirement for affordable housing on the basis of “financial viability”, despite receiving a £50m housing grant. Yet still they somehow managed to find a sizeable wodge of cash to build this superfluous viewing platform, a redundant green garnish to join the peninsula’s infrastructural vanity projects.

• This article was amended on 11 July 2019. An earlier version referred to Ravensbourne College, which is now Ravensbourne University London.