I hate to say this, but the quality of life in the Bagel has crashed in a Harvey Weinstein-like way. The city has always had a sort of rollercoaster feel, its ups and downs driven by Wall Street and budget cuts, but its present state is the worst I’ve experienced by far.

When I first came to New York, it was the true centre of the world. It was after the war and Europe was in ruins. What glamour there was in the world resided in the city. People dressed to the nines, women wore hats and gloves, and manners were far more important than money. It was a feast for the eyes: Rockefeller Center and the chic crowds that skated on its ice rink; the beautiful women shopping on Fifth Avenue; the black-tied swells emerging from the Stork Club and El Morocco; the preppies and Joe Colleges under the clock at the Biltmore.

Palimpsests of the old place survive here and there, and revive memories of youth. A lonely steel diner, an old cigar shop in Brooklyn still advertising five-cent smokes, old tenement neighbourhoods, still crowded with pushcarts, now selling halal food. Chinatown still stinks of garlic and the diamond district is still packed with Hasidic Jews plying their trade, but Tin Pan Alley has gone, as has the music. Now and then a street corner evokes memories of past loves, but the city that was gritty and glamorous is no more.

On the Upper East Side, where I live in a 1920s building, things are as bad as they are downtown or over on the West Side. It’s the people, stupid, not the place. Never have I seen a less glamorous or worse-looking bunch, at least not since I was in Tirana back in the early 1970s. Women and men are short and squat. Women wear leggings and trainers and men wear ghastly docker shorts and tight sleeveless T-shirts that accentuate their obesity. Their bulging calves emerge from very large trainers. It is a horror show like no other.

Fifth Avenue is now a no-man’s-land because of the gawking tourists. Further west, the sleazy shops that sold cheap sex magazines and videos, and made Times Square naughty and unique, have been replaced by giant Apple Stores and mega shops that sell paraphernalia emblazoned with professional team insignia. Peepshows and cheap movie houses are gone, as are fast-food joints like Horn & Hardart.

Once upon a time, the Camel man would exhale a ring of smoke under the logo ‘I’d walk a mile for a Camel’. Now ads are everywhere, deafening and blinding in intensity. Cabs are cramped and impossible to see out of, and cabbies don’t speak English (Urdu will do or pigeon French). The place is hell.

Glamour apart, what I mostly miss are the chic restaurants and nightclubs. The latter no longer exist; the former are packed with badly dressed people whose manners are even worse. New Yorkers have always been loud, but they used to be loud in a sweet, drunken Irish way. Now the streets are loud in an aggressive, menacing way. The jungle has come to the city. Bookstores are rare, mostly replaced by shops selling lingerie — or whatever women are never seen wearing nowadays.

Once upon a time, the city was a place where people came to escape small towns or suburbs. There were bookstores galore, sidewalk cafés, interesting people to meet, even jazz bands playing in the Village. You could tango right in the middle of Times Square, for God’s sake, and after meeting up with some southern belles at the Biltmore, I’d always go up to Harlem, where there were after-hours clubs that treated us with special care. (That’s where I smoked my first joint, at a time when the penalty was probably ten years in the pokey.)

Now all of this is gone. Finished. Curtains. Minorities are the majority in the Big Bagel, and everything is done in their name. City payouts on lawsuits and claims have topped $1 billion a year. People have collected on civil-rights violations, medical malpractice, police wrongdoing, vehicle collisions, defective roads and pavements, water-main breaks and, of course, wrongful imprisonment. As I recently wrote of gigolos, we’re in the wrong business. All one has to do is stop speaking English, fall over on the pavement, and you can claim $5 million for your troubles. (Like the daughter of the African-American civil-rights leader Al Sharpton, who is suing the city for $5 million after purportedly injuring her ankle on a Soho pavement, but was subsequently photographed climbing a mountain in Bali.)

And speaking of jail, Bartle Bull III, as he’s know over here, has made a great documentary, Cradle of Champions, about the Golden Gloves tournament, which amateur boxers compete in each year. It involves more than 500 mostly black and Hispanic youngsters, who are coached by ex-Marines or firefighters who teach them never to say the N- or F-word. Ironically, almost none of the tough kids ever lands in jail or gets into drugs. They live clean, productive lives and it’s boxing that makes them do it. More ironic still is the fact that the city is closing down the gyms where these youngsters train.

I think it’s time for me to return to London. If Brexit happens, I’ll be back in a jiffy.