You either haven't read the book or you you misunderstand how much of the book is Austrian economics. Yes, modern Austrian economics is considered fringe. However, historically the foundational results of early Austrian economics has been fully integrated into mainstream economics. From Wikipedia (https://en.wikipedia.org/wiki/Austrian_School):
> Among the theoretical contributions of the early years of the Austrian School are the subjective theory of value, marginalism in price theory and the formulation of the economic calculation problem, each of which has become an accepted part of mainstream economics.
> The art of economics consists in looking not merely at the immediate but at the longer effects of any act or policy; it consists in tracing the consequences of that policy not merely for one group but for all groups.
> Among the theoretical contributions of the early years of the Austrian School are the subjective theory of value, marginalism in price theory and the formulation of the economic calculation problem, each of which has become an accepted part of mainstream economics.
Hayek was considered partly Austrian and he got the Nobel Prize in Economics in 1974, well after this book was written. (https://en.wikipedia.org/wiki/Friedrich_Hayek)
The core lesson of the book is fantastic:
> The art of economics consists in looking not merely at the immediate but at the longer effects of any act or policy; it consists in tracing the consequences of that policy not merely for one group but for all groups.
This is not fringe at all.