Thinking in black and white keeps us from gaining an accurate model of reality. There is no good or bad. We can only draw conclusions based on what we regard as virtues. For example you might say that health is good. But what about the health of vermin? A better definition doesn't help here. You will always find good and bad aspects about a situation. And then you'll find that calling them good or bad is the same mistake again.
Thinking in black and white includes to say that one thing is better than another one. When talking about progress we often assume that the situation today is better than yesterday. We've got running water, medical care and smartphones. And all these things seem to make life better than it was before. But as we all know deep inside, it's not. Not only from an environmental perspective.
So what has this got to do with minimalism? It leads to a new definition of progress. Or more precisely; a new function of progress, which is to explore possibilities. New inventions are not being made to improve conditions, they are merely toys in a playground of our imagination. And this insight has fundamental impact on our consumption behavior.
We don't consume because we have to as it makes life better or easier or less painful. Nor does it make us happy. Every purchase is simply an investment into the further development of a product or service.
From this perspective it seems rather odd how most people invest into fashion, entertainment and fast food.
If you don't know what endeavors to further, just let it be. That's frugality. You will find that living that way leads to real happiness.
But maybe you discover that you want to spend money on music or literature. Or charity. Whatever you think of as good. Although you should be aware that this is the pitfall.