I think it is an additional iteration of previous talks
Yeah well. Rebase 2020 got delayed and moved from summer to November. By now move semantics for Nim are kinda well established. The newer things covered in this talk are:
Copy elision is a form of borrow checking.
Nim's IR is Nim's AST and easily inspectable via --expandArc.
How ARC/ORC give Nim a cost model suitable for hard realtime programming.
I like the new unofficial motto, but it suffers from the same problem as the old one. Good and bad in design are hardly objective, and the subject of much debate. Reasoning from first principles sounds great; what are these first principles? Reasoning by analogy is a lot like walking on thin ice, so you only want to do it when you have to.