I do agree that if it was being offered as a panacea for all modern woes there'd be reason for harsher scrutiny, but as it stands, it's just some blogger opining that having less might help a bit since they believe it's an unfulfilling task for the amount of time and effort.
Also, it's not as if this blogger is the only person to suggest minimalism; there was an article on HN not too long ago about how minimalism is kicking up in Japan - a casual search for minimalism will show that it's an idea with some following that is a style of philosophy more than anything really.
I'm not sure why this prompted such a harsh reaction, since it's just a fluffy article.