I've seems hundreds of different projects using Maven and more or less every pom.xml looked the same. Onboarding took minutes.

The first few Gradle projects I've seen looked completely different, one project contained more Gradle configuration than actual source code.

And it becomes worse and worse, as every major Gradle version adds new stuff on top.

I can also checkout an old Maven project and it will probably work with a recent Maven version.

With Gradle, not so much. Breaking changes left and right...