AWS is very heavy on Rust internally for core services.

EC2 (lots of embedded work on servers), IAM, DynamoDB, and parts of S3 all heavily use Rust for quite a few years now already.

We can move really fast with Rust as compared to C, while still saving loads of compute and memory compared to other languages. The biggest issue we've hit is the binary size which matters in embedded world.

Linux has added support for Rust now. I don't think Rust's future supremacy over C is doubtful at this point.

AWS might honestly be the biggest on Rust out of all the FAANGs based on what I've heard too. We employ loads of Rust core developers (incl Niko, who is a Sr PE here) and have great internal Rust support at this point :). People still use the JVM where performance doesn't matter, but anywhere where performance matters,I don't see anyone being okay-ed to use C over Rust internally at this point.