We use Elixir + Rust in a few select places. But the majority of our Rust code is services that are purely written in Rust.
We use Rust over Go, not only because of the garbage collection issues, but because it's truly a better language in almost every way (once you learn it!)
I will say, Go is much easier to pick up, but in exchange you pay in the long term having a language that actively works against you when you start working on more advanced programs, and a mountain of code that's accumulated over the years that you have to maintain.
We work on high concurrency systems here, and I very much enjoy not ever having to think about "is this thing thread safe" because the compiler is checking that for you. I love being able to use the type system to offer my co-workers powerful, but difficult to misuse libraries. I like having sensible abstractions around concurrent execution.
Like, for example, if you create a channel in go, and for whatever reason, don't try to read from the channel, or give up (because you're racing a timeout), then the goroutine that tries to write to that channel will block forever and leak. In Rust, if you try to write to a channel where there is no longer a receiver, the write to channel will return an error, which you can then choose to handle, or simply ignore depending on your use-case. Of course, you can be wise and allocate your channels with a capacity of 1, but you can also just completely forget that, and start a steady leak of goroutines for the lifetime of your program that the garbage collector won't save you from!
Want to execute many futures with bounded concurrency in Rust and collect the results back into a Vec, but give up if any of the futures fail, or if a timeout is elapsed, and also make sure that all allocated resources are properly dropped and closed in the event that any errors happen? Just combine a futures::stream::StreamExt::{buffer_unordered, collect}, and a tokio::time::timeout, and in a few lines of code you've done it.
Want to do the same in Go? Spawn a pool of goroutines I guess, distribute two channels, one for sending them work, one for receiving work, and don't forget to throw in a WaitGroup, pass a context along to all the goroutines, make sure you don't forget any defers, if you are using a shared resource, make sure it's thread safe, or make sure you're locking/unlocking the appropriate mutex, make sure you size your result channel appropriately or you might leak goroutines and any allocations they hold if your main goroutine that's spawned all that work timed out waiting for the results to come in. Is there a library that does all this for you in Go? I googled "golang run many goroutines and collect their results" and looked at the first page of results, and it's basically the above...
It is no surprise then that we've picked to use Rust pretty seriously. When you're looking to build reliable systems with serious speeds and massive concurrency, you pick the best tool for the job. That for us is Rust, not Go. And for our real time Distributed systems, we pick Elixir, because BEAM/OTP is just so dang good.