In fairness, the post specifically mentions Amazon and Cloudflare, which are using Rust largely for backend stuff (though also for lower-level systems-y stuff, and I think Go is also a favored backend language at Cloudflare). But yes, other large tech companies (Google and Meta come to mind) are using Rust primarily for the lower-level systems-y stuff, where Go isn't an option and the alternative to Rust is C++. These applications are also less likely to need async and so don't have to deal with that set of rough edges.