That's the full context of what I was saying. Copyleft is a hack for copyright. In a world where copyright is enforced, RMS doesn't consider the neutral ground of public domain licenses (like the popular MIT and BSD licenses) good enough. They do nothing to solve the problem of proprietary software.

The GPL is entirely dependent on copyright. Rather than pretend copyright doesn't exist, the GPL turns it in the other direction. By violating the GPL, Copilot is still violating copyright.