How much less allocation rate? Value types are an important thing and fortunately they are coming to Java as well. But they don't decrease allocation rates nearly enough in every kind of software. They may be a necessity in games/certain computations/low-lat trading, but for a typical web server they don't matter all that much - people are using identity having objects in value typed languages the same way here. Especially that with thread local allocation buffers in Java single-use object allocations are not particularly expensive to begin with - live objects are evacuated and then the whole buffer is reset.

So unless you claim that there is no software in Go/C# where the GC is the bottleneck, no, the problem absolutely doesn't solve itself.