The article mentions that the high degree of ultraviolet light emitted by Proxima Centauri and Trappist-1 stars would create large amounts of carbon monoxide wh

The article mentions that the high degree of ultraviolet light emitted by Proxima Centauri and Trappist-1 stars would create large amounts of carbon monoxide which would bind to hemoglobin suffocating an oxygen breathing lifeform. This is an assumption. I might have to read the book you linked, it looks very interesting, but I think lifeforms that have evolved to not use hemoglobin in their circulatory systems isn't that far of a stretch.