The cool thing is that compared to many languages/platforms, Java already has an excellent module system. Just look at the horrible hacks you have to go through in C++, Ruby or Python to manage multiple projects written in different versions of the language or with different versions of dependencies are just ridiculous, especially if you're developing on multiple platforms. Oh, you want to deploy it too? Have fun.

Let alone the IDE support. I think it's truly amazing that I can make a project with 3 different JVM languages and get instant IDE autocompletion and warnings when calling methods between those languages. The source -> .class -> .jar thing has turned out to be a remarkably visionary design (or just a very lucky hit). For comparison, C# still compiles and "tools" that much slower because .class files are missing in the pipeline.

It's a testament to some of the true goodness of Java, despite its unpopularity in hipper circles, that they don't think a Maven-managed folder full of JARs is good enough.

Of course, this is really a JVM thing and you'll also get it if you use a different JVM language so you can actually get the best of both worlds.

Practically speaking, Maven (the executable tool) and pom.xml (the language) create a hot dependency mess when projects get past the toy stage. Maven makes most simple things impossible and a few challenges trivial. "Hamstrung" is the word that comes to mind. Coupling a declarative, own-the-world, XML programming language with innumerable slap-dash/poorly maintained plugins is the pits.

All that said, maven repositories and the groupId:artifactId:version:type:classifier organization of modules are really genius. As you say, this genius shines in IDE's where, as just one example, you get nice binary/source .jar distributions automatically downloaded to your local repo. Having an IDE's debugger be able to seamlessly and accurately step through 1st party java sources and 3rd party source .jar sources is always so impressive to me.

Gradle (and Ivy before it) help paper over the pain and expose the good parts of the maven ecosystem. I have some gripes with Gradle, but after seeing it in action (and now that IDE's can grok its project configs) I'm so happy to be ditching maven/plugins and hand-written pom's for the most part.

Java needs a holistic dependency management/dependency injection/artifact repository/publishing workflow rethink where well-defined concepts like semver are enforced in the version numbering scheme, making it easier to express "safe" legal version ranges in transitive dependencies.

Because Maven (the tool) offers XML as the language, we can put any other language atop it, e.g. with https://github.com/takari/polyglot-maven we can use Clojure, Groovy, Ruby, or Scala as the language. Gradle offers only Groovy, nothing else, so we don't have any choice over how to interact with the build API.