I think I know what kind of developers you deal with
Rust has an amazing multi threaded ecosystem. In the case you are cpu bound and you use parallelism to speed processes you should talk about rayon. It follows Intel’s cilck philosophy and is just amazing.
In case you are IO bound and you use multi threading to hide latencies and improve response time, have a look to futures and tokio. This is absolute alien for a C developer as there is nothing close to a future at this level. They need to understand that you are getting a very high level abstraction and paying close to nothing for having it.
I hope you enjoy the research you are doing, don’t forget to share the outcome!