Valhalla is pretty big. Goetz described it as pulling on a very long string. It's going to touch everything in the JVM, including reifing generics, although as I understand it, erasure of Objects may be here to stay for the language.
What's broken in the JVM isn't erased generics but instead runtime reflection that is a lie due to erasure. Type erasure though is definitely an example of Java getting something very right for the wrong reasons.
Furthermore, runtime specialization (as opposed to compile-time) would seem to require reified types. So that further confuses things. But you can definitely have reified types without specialization, which I think is the point that you are trying to convey.
Either way, CLR and C# did it a long time ago, and in the same time period when Java acquired its type-erased generics.