Minimalism wasn't invented yesterday. To a large extent we in the Western World have the famously cluttery and richly ornamented Victorians to thank for the concept. The endlessly dusted off advice of William Morris "Have nothing in your houses that you do not know to be useful, or believe to be beautiful" is from a lecture of 1882. Mies van der Rohe's "less is more" repeats a line in a Browning poem of 1855.
Morris, though, was not advising to own few things, but rather to reject tawdry objects of industrial production and instead to develop an appreciation of the craft and aesthetics of well made, well selected furnishings, objects, and art. The linked image shows two views of the sparsely furnished but anything but plain hall of 1877-1879 in the studio/house of his friend and fellow advocate of this ideology Frederick Lord Leighton: this is what Morris meant in his advice, not to live like a Buddhist monk but like a rich man with informed taste.
The idea that throwing out all of our shit will make us better and happier people seems to miss the mark. It just replaces the urge to buy needless ugly shit with the need to throw it all out and feel better about oneself. For me, the better thing is to select things with care, with an eye to aesthetics and utility (whether fresh flowers that may last a few days or a table that you may see every day for years or perhaps decades.)
A generation of two has been ruined by episodes of "Hoarders" to think that stuff itself is the disease and avoiding stuff makes us better and healthier. They mistake being ball's deep in food encrusted Burger King styrofoam clamshell boxes and cat shit and magazines and advertising flyers as the same as having a collection of a dozen Italian Renaissance bronzes in a large house. The one thing is shit and the product of a diseased mind, the other is the expression of someone with some money and a highly specific taste (whether good or bad in the selection.)
Trimming down a wardrobe to the bare essentials of a college student backpacking the world for two years doesn't make you a better person, it just makes you a person with few clothes. If you use the clothes, why not have many? Why should the rest of us care and scold?
I would be bored as fuck with everything painted white or French gray and rooms furnished with Barcelona chairs and one large painting on one wall in each room, with a lamp or two, and a ceramic bowl of jet black river stones. My life isn't so hectic and mad that I need that kind of design lobotomy lab at home; I can appreciate the qualities of the space for people who appreciate and understand and enjoy that look, but I need more chaos and color and control of another sort. I might even need a few kinds of kitchen spatulas.
It's not *things* that are anyone's problem unless the things are *stupid shit* without any beauty or any purpose, even if that purpose is only to delight. Advising people who don't have a clue as to why they bought the shit in the first place to just chuck it all out and feel morally superior to their old self seems some very half-assed feel-good advice.