I think an interesting distinction is this: it's not that 90% of the typing you do is necessarily useless, it's that it's been done before. Copilot is, in a sense, drawing from a corpus of prior work. In that way you are kind of using it as if you found a published library for your more specific use cases. So it's allowing you to draw on prior work without necessarily having external packages split up with the granularity of many variations of functions (which, ideally, would allow you to pull in exactly what you need from prior work, but would certainly be onerous in practice).
That being said, I've never used Copilot myself, so I can't speak very confidently about it. But from what I've seen, it kind of allows you to incorporate every library that's ever been made open source into your project, but in a more granular fashion. Which naturally would save you some typing :)
P.S. I realize Copilot isn't necessarily copying other code verbatim, though I assume pretty often it basically ends up doing that, at least in pieces.
That being said, I've never used Copilot myself, so I can't speak very confidently about it. But from what I've seen, it kind of allows you to incorporate every library that's ever been made open source into your project, but in a more granular fashion. Which naturally would save you some typing :)
P.S. I realize Copilot isn't necessarily copying other code verbatim, though I assume pretty often it basically ends up doing that, at least in pieces.