In a way, it's no different than an artist walking through an art gallery then going home, inspired, to paint a dark portrait a la Rembrandt

What is ok if they do something different, and not ok if they just repaint the same thing, depending on the source. And this software surely repaints a lot of the same things, so the only question is the source.

In such analogy, Copilot is no different than looking at someone code a bubble sort and then later doing one yourself. Some people on this forum had issue with that.