At the moment, the general impression I get from people working at Amazon is "Join for the experience, get it on your CV, move on after a year". This is even across departments and countries. The wife of a very good friend who lives in China is working there since nine months in some kind of operations role, and made up her mind months ago that she wouldn't take it any longer than a year. Here in Berlin, I just recently talked to a dev who left exactly a year after he started. He said it was interesting seeing the whole AWS machinery from the inside, and there was quite a lot to learn in terms of process and management, but shoving around legacy Java was just not worth it.
For a technology to be legacy, I think it needs to be stale and falling out of use for new projects. I don't see that with Java. New releases with new language features are being released at a faster pace than ever, and companies are still building new products on it.
Java hits a sweet spot of performance, tooling, and productivity that few other ecosystems can. It's biggest competitors are probably C# and golang, and, for various reasons, it is holding its own just fine against them.
If you remember Duke, you're old. I still remember when Sun was going around holding Java events, touting the advantages of Java, with Duke shirts, mugs, etc.
