One of the biggest complaints I hear about Groovy is that it is a dynamically compiled language — not that any dynamic language or platform could ever become popular or useful (Python, JS/node, Ruby, and more). However, Groovy isn't just a dynamic language; it's an optionally typed language. This means you can mix and match the power of a dynamic language with that of a statically compiled language.
Another complaint I often hear once people realize that Groovy can be statically compiled using an annotation at the class or method level is that it feels bolted on. To address the second concern, I recently released a Gradle plugin called Enterprise Groovy, which can be found on my GitHub page.