I am a life-long student of the language, and for those who are, and who use it in their Christian ministries, the difference between using Shen and ShangDi is of great interest and it does matter to know the difference when working with the Chinese in their homeland.
Regardless of the article(s) you cited, ShangDi is not only ancient and pre-Christian, referring to Monotheism in general, it is also in current usage, and even non-Christians in China know that the current usage is referring specifically to the God of Abraham, Isaac, and Jacob, the God of Christianity. There is no other current usage of it.
I defer to your infinitely greater knowledge of the modern language. (Not hard, since mine is zero.)
I only commented because I’d run across the term ShangDi (or variants) before in reading Chinese history. It was in use long before Christianity came to China, and probably long before Christ.
It is also interesting that the term in (earlier) Chinese had pretty much the same meaning as Allah in pre-Islamic Arabic, referring to a distant, not particularly involved with humanity Supreme God whose existence by no means ruled out the existence of other gods who played a much greater role in the everyday life of the people. I believe this POV is known as henotheism.