Yes! I suspect (but I don't know for sure) that C# has the highest performance sealing of all the VM-based languages with a tracing garbage collector. structs, Span<T> and ReadOnlySpan<T> for type-safe access to contiguous regions of memory allow us to do a lot without touching the heap. C# also has hardware intrinsics for non-cross platform SIMD instructions if you're interested in that kind of thing.
Perhaps it can be manually optimized the best indeed, but the JVM still has a better GC if I’m not mistaken.
Value types are indeed very cool, and I really hope they will get implemented sooner on the Java side as well. Just as a note, Java recently got a SIMD API as well.
