These three quotes from the author Grey seem to be addressing the issue of cultural appropriation, and the author's argument is that cultural appropriation is not acceptable.
The first quote suggests that if the definition of cultural appropriation had stayed narrow, it would be easy to defend. This suggests that the author may believe that the definition has become too broad, leading to confusion and debate.
The second quote seems to argue that those who demand the right to appropriate elements of other cultures are acting foolishly and without regard for the social consequences of their actions. The author may believe that cultural appropriation is disrespectful and can lead to harm for marginalized groups.
The third quote suggests that the concept of "pure" culture is a fallacy. This may be the author's way of arguing that all cultures are constantly evolving and interacting with one another, and that there is no such thing as a culture that is entirely separate from outside influences. Therefore, it may be inappropriate to claim ownership over elements of a culture and prevent others from appreciating or incorporating them.