The reason that it's popular is that it's immediately clear that Rust's model of memory safety without a GC and safe concurrency is the best way to create a pro

The reason that it's popular is that it's immediately clear that Rust's model of memory safety without a GC and safe concurrency is the best way to create a programming language since it unifies the memory safety of GC languages like Java, the efficiency of C and the concurrency of message-passing systems like Erlang in a single language that has none of the drawbacks of those systems. Before Rust, everyone simply assumed that it was impossible to create such a programming language since it would have otherwise been what everyone used, and now that it turns out that it's possible, it's clear that it's the best solution and what should be used in the future whenever possible.