> there are umpteen alternatives (gradle etc)
there was ant (build tool) then came maven which is much more flexible and contains dependency management capabilities (and _is loved_ by many) nothing to add that the parent did not already say. Then came gradle which has faster build speed and features like incremental builds and a Groovy based configuration.
pip did not ship with python for a long time, and has problems of its own.
You make it sound like adding Apache Groovy for configuration to a build system is an improvement. When build systems with a declarative config language, such as make, ant, and maven, replace procedural build scripts, that's the improvement. Using a procedural language like Groovy instead is a large leap backwards because it encourages programmers to add unneeded procedural features to build scripts, creating an unmaintainable mess.
> a huge and over-complicated xml-based system
It was an attempt to show that there are not 'umpteen different alternatives' and the ones that exist, do so for a reason. Though looking back, I should have worded it in a better way.