Rust has its uses but why would you write infra code in Rust when Go is used for most of it, and is just much more ergonomic and fast to work with. The iteration times with Rust are quite detrimental. On the other hand, most of k8s' ecosystem is in Go.
I don't like commenting in language-war territory things but I found your comment surprising. "Rust or JVM" for infra isn't a dichotomy I would expect.
They didn't have particularly great reasons to migrate at the time besides the team wanting to write rust. That article is just trying to provide validation
"With the Go implementation, the Read States service was not supporting its product requirements. It was fast most of the time, but every few minutes we saw large latency spikes that were bad for user experience. After investigating, we determined the spikes were due to core Go features: its memory model and garbage collector (GC)."
The entire point of writing rust is that you're trading writing speed for runtime safety. It takes longer to write but you can guarantee you're never going to have a nil pointer panic or race condition.
Unless you're doing something super weird your infra code is gonna be running for way longer than you spend writing it so who cares if it takes an extra 20%/30%/50%/whatever time to write?
Eh, I don't think iteration times in Rust are nearly as bad as you think. During a realistic development loop compilation is <1s in most situations thanks to incremental compilation and tests are fast unless you have synthetic slowdowns such as sleeps or IO (which would effect both languages equally).
I don't like commenting in language-war territory things but I found your comment surprising. "Rust or JVM" for infra isn't a dichotomy I would expect.