>The JVM itself has a certain amount of unavoidable overhead
That is not a "certain amount of overhead" but the inherent incompatility with the modern hardware. With Java writing cache-friendly code is extremely difficult: boxing and indirections are encouraged while primitive types are cumbersome and value types are possible only through the direct byte manipulation. Memory overhead is enourmous. A simple collection like a hashmap of short strings can have up to a 75% overhead.
The JVM itself has a certain amount of unavoidable overhead, but even if it was e.g. 10x slower than native code at best, I don't think that's the main problem. I've used systems that were more than 10x slower in benchmark-terms and had less than 1/10th the memory, yet felt much more responsive and performant. The problem is the culture that encourages this massive resource waste and selfish conservation of developer's time --- at the expense of everyone else.