If you can encode your request processing patterns in statically sized types, then you can get the same high-level memory allocation behavior on both platforms. Arguably Rust makes this a bit easier. (Though I have no idea how much of the concepts of mechanical sympathy made it to mainstream Java.)

If you have some kind of super vague complicated patchwork of plugins that all contribute to processing, then the JVM seems to be the more convenient choice.

https://martinfowler.com/articles/mechanical-sympathy-princi...

Indirect evidence, but parts of AWS and cloudflare have been running Rust in production for close to a decade now and neither company looks to be itching to move services back to Java.

> other network services better than the JVM with its hot spot?

JVM hotspot optimization is just band-aid for something Rust does always everywhere naturally? Assuming that you use lifetimes etc properly and not going to Arc rampage.