Low attendance at two art institutions was blamed last week on buskers outside. We went to investigate…

It’s a mournfully grey day in the heart of London. Only a tiny number of tourists in heavy overcoats are braving the bitter wind cutting across Trafalgar Square. Even the pigeons have stayed away.

Amid this bleak monochrome scene, the only flashes of colour are two floating Yodas, one dressed in bright green, the other in neon yellow, who are performing as “living statues” – although it has to be said neither is particularly stationary.

“How’s business?” I ask Felix, the green Yoda. “No fun,” he mumbles from behind his mask. ”There are no tourists because it’s raining all day, every day.”

Ah, the weather, that perennial British gripe. Yet copious precipitation is not the reason the National Gallery has seen a 20% drop in visitors in the last year. Nor why, just around the corner, the National Portrait Gallery is 42% down.

One theory put about is that potential customers have been discouraged by the street performers, like Felix the green Yoda, that populate the pedestrianised space created in a major redevelopment in 2003.

The halting of traffic on the north side of the landmark was an attempt to turn a busy roundabout into an elegant square along continental lines. But Sir Nicholas Penny, the director of the National Gallery until 2015, came to lament the change, claiming that it had led to the “trashing of civic space”.

Two years ago his successor Gabriele Finaldi also complained about buskers and living statues. “It would be nice for Trafalgar Square to become an attractive part of London,” he said. “It would be lovely to make it a place that works for us.”

But is it a place that works for the public? “Yes,” says Adrian Robbins, from Wrexham. “I wouldn’t have stopped here if it wasn’t for the performers.” Would he be going into the National Gallery? “No, because I don’t have time.”

Adrian and Martine Torjussen agree. “I think the performers and buskers add something,” says Adrian. The couple are up from Devon with their son, and have just been to the National Portrait Gallery.

Martine draws an unfavourable comparison with the portrait gallery they had recently visited in Oslo. “They had an area where you could pick up pencils and papers and draw a portrait. And nice seating so that you could sit down and gaze at the pictures. Whereas here you feel like that you’re being processed through it as quickly as possible. That won’t bring us back in a hurry.”

Just then a plangent voice and sweet guitar arrives on the icy wind. They belong to Wayne Aviri, a busker who’s been plying his trade on this concourse for the past three years. Did he think his streetcraft was getting in the way of great art?

“No, I think if anything we attract people to the area. You’ve got people busking outside Tate Modern and it doesn’t stop people going there.”

In fact, Tate Modern saw an 11% drop in visitors last year, but its sister institution Tate Britain recorded a 53% increase. The V&A also enjoyed a significant boost. Much of the variation is down to the popularity of particular exhibitions. For example, one reason the National Portrait Gallery seems to be in the doldrums is its bumper year in 2016, thanks to the Vogue exhibition.

Facebook Twitter Pinterest ‘Pokemon’ entertains a two-year-old in Trafalgar Square. Photograph: Andy Hall/The Observer

However the vast majority of exhibition-goers make a conscious decision to go to a specific show, rather than happen across a gallery and choose not to go in because of the quality of nearby street performers.

A bearded artist on his knees, creating pavement graffiti constructed out of coins, makes the point with irrefutable logic: “Most people who are coming to visit the gallery are coming to visit the gallery.” Entranced by this gnomic street wisdom, I listen as he continues: “I would say that what goes on outside the building shouldn’t affect the experience inside the building.”

Who is this towering sage? “I go by the name of Friend,” he says, sounding like a character from a morality play. But it turns out what he really wants to discuss is saving the planet.

Reluctantly I excuse myself, and ask a security guard at the entrance to the National Gallery what she thinks about the idea that street perfomers are keeping visitors away. “I’m afraid I’m not allowed to talk to you,” she says. “You’ll have to speak to the press office.”

Yes, but does she think it’s true? She shakes her head and pulls a face that seems to suggest that she’s never heard such nonsense.

In any case, if some people had stayed away, would that be so bad? “To be honest,” Adrian said, “crowds would keep me away.” This, of course, is the holiday paradox: everyone wants to go to the deserted beach. And what most of us want from a gallery is a bit of space and time to appreciate the works.

Later I spent a pleasurable hour taking in the National Gallery’s masterpieces, enhanced by the absence of throngs shouldering me along. Too often visiting a major exhibition is like filing past the tomb of a dictator a few days after his death.

Perhaps, for art lovers, falling visitor numbers is to be celebrated. Emerging from my unhurried encounters with Caravaggio, Turner and Velázquez I could see David Shrigley’s giant sculpture of a human hand atop the fourth plinth. Its long thumb pointing triumphantly upwards. Suddenly even under the clouds, Trafalgar Square, street performers and all, looked really quite beautiful.