I’ve used Geefix for installing floating cabinets in the bathroom, which weren’t mentioned in the article. They claim to hold a lot of weight: https://www.geefix.com/
I think the goal of this article was to highlight options that US buyers would have at their local home improvement or hardware stores. I've seen every one of the recommended items at Lowes or Home Depot over the past several decades, and have never heard of nor seen Geefix (which, btw, looks like a simple variation of the pull toggles highlighted in the article).
Geefix are easy to source on Amazon and other online retailers. But yeah, not at Home Depot or Lowe's. But then again, most wood workers (target of audience of that website) probably already source the tools and materials they use from a variety of non-big-box stores.
