Gradle introduced a lot of breaking changes in version 5 (and subsequent versions as well) and I stumble across old, unmaintained code on github from time to time that requires gradle version 4 to build. So IMHO this package isn't "unneeded". Also not sure why it bothers you so much you want it deleted.
On Sat, 2023-07-08 at 15:52 +0000, notify@aur.archlinux.org wrote:
MarsSeed [1] filed a deletion request for gradle4 [2]:
Unneeded old gradle v4 package from 2019.
Current version of gradle is v8.2.
Nothing depends on this legacy package.