JVM is an awesome piece of technology. And you can do robotic control systems to high-frequency trading systems with it with careful programming.
But I've seen a lot of Java code running in production suffering from latency jitters and needing continuous profiling and optimization by a small group of performance engineers while the majority of application engineers keep adding to GC load.
> For this specific use-case, I don't think there is really an alternative, except for specifically a hand-crafted system
Yes, but I think the handcrafted system doesn't need to be very complex. It can be quite simple and easy to understand and tame to your needs as your scale and complexity grows.