> To place intrinsic value on nature, then, is ultimately nihilistic and profoundly anti-human.
This statement only makes sense if you hold the view that human and nature are two separate things. This is a narrow Western viewpoint, whereas the Eastern mindset skews towards nondualism (https://en.wikipedia.org/wiki/Nondualism). The human is seen as an interconnected part of all the nature around them, not a separate thing. In this mindset assigning value to nature is a path to assigning value to oneself.
For example, many cultures with a more collectivist mindset have historically derived great personal meaning and value in their lives from the idea that they were protectors and stewards of the nature around them, even as that nature protected and sustained them.
In my opinion, setting the human apart from nature (and in some cases in opposition) is it's own path to nihilism. The more we build this wall of separation the more quickly we fall down slippery slopes to the darkest areas of modern Western thought. With few other ways to define the value of a human, we attempt to define the value of humans relative to the value they produce for each other, and then we independently isolate human value by ranking humans in order of most value to least value, etc.