Especially when you consider that on one end some companies forbid their employees to even read GPL source to alleviate the legal risks of accidental copy, and

Especially when you consider that on one end some companies forbid their employees to even read GPL source to alleviate the legal risks of accidental copy, and on the other hand, there's the common practice of clean room implementations for more or less the same reason. If brains can be tainted by reading code, how does that not apply to Copilot?