Ultimately, almost all of the cultural output of mankind is rooted in borrowing ideas from elswhere. I am a chef so I am going to use a food analogy: consider spaghetti with meatballs.
Pasta was originally Chinese. Tomatoes are from Central America and were unknown in Italy before colonialism. The dish itself was invented by Italian immigrants in New York. The entire thing is appropriated and inauthentic, but it's good if it's made right.
That is how cultural creation works. Artists are constantly influenced by the things around them, the things that came before, and the things they have experienced. You can't ask them to ignore a subset of their experiences because it came from another culture.
The end result of hypersensitivity toward cultural apropriation will be to put artists in boxes and less work of merit will be created. We are in an awkward moment in America where everybody wants to be mad about everything. It is true of both the left and the right.
If we give that impulse full flower, we will destroy ourselves.