I think this article (and some of your points too) are conflating minimalism with simplicity. Minimalist is buying 1 Kindle and putting all of your books on it

I think this article (and some of your points too) are conflating minimalism with simplicity. Minimalist is buying 1 Kindle and putting all of your books on it and then selling them. This is more expensive. Simple is keeping your books you want to read again and getting rid of books you've read and aren't going to read to reduce your bookshelf space. Then get a library card and check out books to read from there. Less $ and simpler, though not necessarily the most minimalist you can be. I think minimalism is one aspect of simplicity, but not the only one. Simplicity also involves practicality, economics, sustainability, etc.