Swift was designed as C, Objective-C and C++ replacement from the start, and those statement have not yet been removed from its official documentation.
Naturally they couldn't tackle everything at once.
If that was the plan from the start I'd expect them to be more careful about dependences on reference counting and implicit allocations. It's more optimized than ObjC, but still has things like loops that iterate over a logical copy.
I take their old statements about replacing C and C++ as the same aspiration that Golang had to be a systems programming language.
Swift has originally been designed as an ObjC replacement, mostly for UI glue code, with conveniences more like a scripting language.
So now they're working on making Swift support more low-level low-overhead code.
https://youtu.be/lgivCGdmFrw