Compiler Languages - What Are the Top 3 Things That Have Made a Significant Difference?

Rust was chosen so that we could enable a bunch of optimizations and having low overhead in general. Top three things I would say would be, struck of arrays,. Never hear that talked about in compiler language, except by Andrew Kelly. Go is the only one that I can think of like a top 20 popularity language today. And guess what goes is known to have fast compile times? It's crazy.