No this talk is about something entirely different, the idea of giving a libc interface to Zig's standard library in order to use it whenever a C project needs

No this talk is about something entirely different, the idea of giving a libc interface to Zig's standard library in order to use it whenever a C project needs a libc dependency and wants static linking. Currently Zig uses musl for that but in a future it could just use its own stdlib instead. Zig can link against libcs without major issues.