The setup instructions for almost [1] every [2] major [3] rule set [4] only provide one (GitHub) url in the Starlark blob you're supposed to copy and paste, so hard to blame users here.
[1] https://github.com/bazelbuild/rules_jvm_external/releases/ta...
[2] https://github.com/bazelbuild/rules_python/releases/tag/0.17...
[3] https://github.com/bazelbuild/rules_java/releases/tag/5.4.0