There is considerable cherry picking along with cultural appropriation going on here. Buddhism has flavors that are worlds apart from what is described in the post.
A spicy example is discussed in the book "Zen at War"[1]. Myanamar and Sri Lanka[2] have their own ultra nationalistic Buddhists movements.
[1] https://en.wikipedia.org/wiki/Zen_at_War
[2] https://en.wikipedia.org/wiki/Sinhalese_Buddhist_nationalism
Obviously there are many flavours of Buddhism and many flavours of Christianity, but the author is simply relating his own experience. I really don't see how cherry picking or cultural appropriation could possibly apply here.
The author picks and chooses aspects of a tradition/religion/philosophy and names the result as the original tradition/religion/philosophy.
Does that help?
I think the author is speaking about a specific tradition of Buddhism, Zen, and is drawing parallels between that tradition and Quakerism. The “picking and choosing” point doesn’t make sense to me from that angle. Are you picking and choosing from Christianity when you talk about Protestantism, for example? His thoughts on Zen are pretty on point.