If you've ever spent some time reading some of the really good cookbooks you'll realize just how valuable they can be. While a 'minimum viable kitchen' may be a misleading title, the author is focusing an audience interested in more gourmet, high quality cooking. The difference between the recipes found in a cookbook by say Thomas Keller or David Chang and those found at recipes.com or even foodnetwork.com are significant for the 'foodie' cooks.

I also think a standing mixer is a luxury, but I've upvoted everyone who's said you cannot ditch the whisk. Whisks are important. Enough said.

Many comments on this thread have been about knives. I've owned quite a few knives over the span of years of professional cooking. A really good chef knife will really only be appreciated by those who cook either professionally or really seriously as a hobby. A soccer mom who chops onions once or twice a week to cook dinner very likely won't know/feel the difference between a 50$ Whustoff or Henckel vs a $250 Shun.

The other important thing to know about knives is if you do decide to spring for a good quality blade, maintaining it is really important. Sharpening with a whetstone with the appropriate grit and honing the blade before each use will keep your sharp edge for much longer.

All in all the article is good. All-clad is hands down the best quality and most durable cookwear out there. Although I don't think using a dutch oven to make sauces is a great idea.