If a software developer writes a program to remember a million lines of GPL code, then uses that dataset to "generate" some of that code, then they are essentially violating that license with extra steps.

The extra steps aren't enough to exhonorate them. It's just a convoluted copy operation.

Is just like how a lossy encoding of a song is still - with respect to copyright - a copy of that song. The data is totally different, and some of the original is missing. It's still a derivative work. So is a remix. So is a reperformance.

Copilot is not a person, it is a piece of software.

Depends on how closely they reuse the code. Writing it verbatim or nearly? Yes.

A human doesn't perfectly reproduce the same code he learned from.

A person with eidetic memory absolutely could do so.