Code being freely shareable and remixable is great. Selling that open source code for profit is not.

I feel like you're missing the forest for the trees here - making code freely shareable and remixable is exactly the purpose of GPL and other free-software licenses, but you can bet that the proprietary codebases Copilot will be used in will go out of their way to prevent any such uses of _their_ particular code snippets.

IMO, the only way to use Copilot's output in an ethically sound way is to only use the output it produces in AGPL licensed projects (assuming that Copilot has not been trained on any non-free software codebases which in itself is a strong assumption).

It's just as shareable on Gitlab, no? And the issue isn't that code is not shareable - it's that a huge corporation is profiting from this code without consent from the developer.

Well, I hope your viewpoint doesn't win the day, because breaching GPL left and right to make some developers life easier opens huge cans of worms.