You are right it does sound really nuanced.
If you asked me…
When you copy someone else’s work they have completed the work for you. In school they called it plagiarizing.
Since we are talking about free and open source then copying isn’t such a bad thing. Which in my little brain says that he (Luke) leveraged all of the Bitcoin Core teams work and added more.
So it’s like having all of them plus Luke work on Knots.
This may be unpopular, but it works for me. Core seems to have one less developer than Knots working on it.