Maybe he meant net advantages. Rust has some advantages (ADTs, no constructors, no overloading, no preprocessor, well thought out set of string types) and some disadvantages (compile times, debug performance, heaps of wrapper cruft to step through when debugging, explicit lifetimes, pervasive type inference, ad-hoc polymorphism, no ABI stability, poor support for dynamic linking, anemic standard library, pervasive one-element-thinking encouraging millions of separate allocations all over the place, culture of simplifying code by adding copying and reallocation everywhere because the borrow checker makes sharing verbose and difficult ("just use clone"), general complexity, dramatic and dogmatic community with a penchant for social media bullying (eg serde, actix)).
What is an advantage or a disadvantage depends on who you are. Personally, I find the disadvantages (as I see them) outweigh the advantages. Others believe that some of those disadvantages are actually good things. And some of them depend on whether you are comparing to C or C++: compared to C, Rust has many disadvantages, but C++ has many of the same disadvantages, and often is worse.
I don't think Rust will ever have more new code being written in it than C and C++ combined. I doubt it will overtake either individually.
What is an advantage or a disadvantage depends on who you are. Personally, I find the disadvantages (as I see them) outweigh the advantages. Others believe that some of those disadvantages are actually good things. And some of them depend on whether you are comparing to C or C++: compared to C, Rust has many disadvantages, but C++ has many of the same disadvantages, and often is worse.
I don't think Rust will ever have more new code being written in it than C and C++ combined. I doubt it will overtake either individually.