As I sat down at this year’s Serpentine Pavilion, I overheard a curious exchange. ‘You mustn’t create art within art,’ said an invigilator frostily. He was telling off Fred Pilbrow, an architect, who had been taking in the Pavilion’s sociable atmosphere with friends and painting a watercolour of the scene. They proceeded to enter a perverse negotiation as the invigilator struggled with the theoretical parameters of his orders; apparently the watercolour may stain the furniture but dry media like pencils aren’t allowed either; actually, all art-making is not allowed in any of the exhibitions, ‘but photography is OK’.

The subject of this exchange, Fred’s contraband watercolour, depicted people in passionate conversation across a table, which ironically is what this year’s Pavilion was designed to encourage. As part of the Serpentine Gallery’s annual patronage of a prominent architect, this year they have chosen the French-Lebanese architect Lina Ghotmeh to design a temporary structure for the summer months, housing a café just outside the Gallery’s south building in Kensington Gardens. Entitled À table, after the French call to start a meal, Ghotmeh designed the Pavilion as an invitation to ‘to convene, sit down, think, share and celebrate exchanges that enable new relationships to form’, and ‘offering a moment of conviviality around a table’. While Ghotmeh’s intent seems unquestionably realised on this buzzing Sunday afternoon, for Fred this conviviality, existing only on the Gallery’s terms, fell somewhat short. Despite its social function, the Pavilion remains a precious art object that must be guarded until the end of summer; it has already been earmarked for sale to a private collector.

Pavilions often attempt to fit big ideas about a building into a small one, and it isn’t surprising that this Pavilion often feels more like a mixed bag of signals for the architect’s good intentions (and sometimes disappointments), rather than a cohesive piece of architecture. The most immediate of these is the ostentatious use of timber for every visible surface, chosen as it’s ‘bio-sourced and low-carbon’. It’s fitting for a space designed to house discussions on our relationship with Earth, yet the timber structure has been stained in a shade of brown that is as convincing as a spray tan. Instead of accepting the colour variations of the natural material, the architect seems more keen to signal the idea of wood than its materiality – to make a show of how they are minimising the environmental impact of an otherwise non-essential building needing to justify itself. Climate-conscious architects often say: ‘The most sustainable building is the one you don’t build,’ but the Pavilion simply doubles down on their environmentalist message.

Continuing this dialogue with nature, the Pavilion’s umbrella-like roof has a concave polygonal shape intended to respectfully avoid the park’s trees, with delicate concertina folds inspired by palm fronds. Yet this is somewhat illegible from the ground, apart from the exquisitely razor-sharp eaves. ‘It seems designed for a top-down view that you’ll never see,’ another architect visitor tells me, who regards it as a rookie error typical of architecture students more preoccupied with the building as an object, rather than a space. Inside the brochure, they helpfully show a computer-generated aerial image of the Pavilion, in case you forget to bring your drone.

But perhaps the biggest blow is the screens that enclose the pavilion, featuring kitsch cut-out patterns of stylised leaves that take this echoing of nature into full-blown caricature, looking like something from a garden centre’s own-brand fencing range. It was made known that this was a cost-cutting substitute for what was intended to be glass-panelling, but paired with an insipid café menu that is inspired by a watered-down version of the architect’s Lebanese heritage, it is perhaps the final straw that tips the Pavilion into feeling like a beach shack in a Mediterranean tourist resort.

Fred and his friends had already gone by now, possibly in search of a convivial space that is less policed. As I left, I happened to catch the Serpentine Gallery’s concurrent exhibition by Tomás Saraceno, which features a poignant film on the hidden costs of the global push for decarbonisation, namely the environmental and social consequences from lithium extraction for batteries in Argentina. Clearly, the Serpentine’s curators have made environmental ethics central to what they preach, yet I can’t help but dwell on the forest that supplied the timber for this seasonal folly. As to whether or not it was cut down for a good enough reason, they seem not to have seen the wood for the trees.