I share the same view, based on the jobs in my area, everyone is using Python to prototype and Java/Scala to productionize, I've also seen Node.js increasingly being used, probably for things that are I/O-intensive and not compute-bounded. Rust could change the landscape for Node/Deno, critical code which is memory/cpu-intensive could be exported to a WASM library or an external dependency that can be called through FFI (though that would be very slow and you introduce the 2-language problem that Julia is trying to fix for Python). Anyway, even if we are in a way better state today than, let's say, 5 years ago when it comes to picking tools for data engineering, I strongly believe that JVM is here to say for a long, long time.