The French couturier — who found fame putting Madonna in a conical bra and helped shape global trends for four decades — shocked the fashion world by ending his ready-to-wear and menswear lines earlier this year.
And in a candid interview with The Associated Press, the 62-year-old — whose signature peroxide quiff has now rather symbolically greyed — explained why.
"Too many clothes kills clothes ... Fashion has changed. A proliferation of clothing. Eight collections per season — that's 16 a year," he said.
"The system doesn't work ... There aren't enough people to buy them. We're making clothes that aren't destined to be worn," he added as he stood beside a mannequin sporting one of his giant, pointy bustiers.
Gaultier gave his grave prognosis on the health of fashion from the newest leg of his acclaimed retrospective, which has travelled from Montreal to Rotterdam to London — and is now in Paris. The scope of the exhibit, from top hats made of human hair to bondage outfits and corsets made of ribbon, showcases Gaultier's brilliance and theatrical flair.
And his launch party — attended by the likes of Kylie Minogue, Catherine Deneuve and Nana Mouskouri — was testament to his enduring popularity.
But the retrospective also feels like it heralds the end of an era. The one-time enfant terrible was once seen as the heir to Yves Saint Laurent, but in recent seasons his womenswear shows failed to impress top critics who judged that his designs now lacked coherence.
"It fits very well that (the exhibit) is now in Paris, at a time when I've stopped ready-to-wear," Gaultier said, without nostalgia.
The designer said that he ended his 38-year-old womenswear line because he was fed up with the non-stop merchandizing, commercialization and marketing that the frenetic ready-to-wear industries demand. Instead, he wanted to concentrate of his profitable couture line, which he presents in Paris in January and July each year, as well as his theatre and cinema work.
"I continue doing the things that I like," he said. "It's almost a luxury, is it not?"
Gaultier isn't the only one disillusioned with a luxury industry that's bursting at the seams. Today, for example, there are some 100 collections presented four times a year in Paris alone.
Dutch design duo Viktor & Rolf gave up their ready-to-wear line this year too, citing similar reasons as Gaultier. They just couldn't keep up with the grueling pace of the industry and wanted to concentrate on couture.
So what is the solution for the fashion-conscious consumer?
It might sound shocking for a designer who's now concentrating on his astronomically-priced haute couture line — but Gaultier's advice is to go to the high street.
"There are labels that do inexpensive clothes very well, like Zara, H&M, Uniqlo. People can dress well for not too much money," he said. "So why go and buy expensive clothes?"
Gaultier, a man known for his cheeky humour, cannot stay gloomy for long.
Looking back through his four decades of creations he recalls the surprising origin of the bustier that first made him a household name in the U.S. —when a certain pop star from Michigan wore it on her "Blond Ambition" tour in 1990.
"It was not Madonna who wore my first conical bra, it was Nana my Teddy Bear. And when I was six, I wanted to have a doll, but my parents didn't find it politically correct for a boy," he said.
Madonna is still very much in his heart — and he defended her against ageist criticism that her fall in this year's Brit Awards showed that, at 56 years old, she should be hanging up her pointy bra once and for all.
"Why do they attack her because of her age, and they don't do it to men?" he asked.
"She got up as if it was nothing and to fall must have hurt a lot. She could have killed herself," he said. "She's a miracle because, well, she's Madonna."
The famed bra — and his Teddy Bear, Nana — can both be found in the Grand Palais exhibit in Paris, which runs until August 3.
Thomas Adamson can be followed at Twitter.com/ThomasAdamsonAP