The macport version of gradle is always outdated.
It would be nice if an active gradle developer and macport user step up to maintain the port. Please see the macport ticket calling for abandonenment of the current, inactive port maintainer.
I was the maintainer of the gradle macports port in the past. I’m currently in the process in giving up my maintainer status for several ports. The reason for that is, that I think their are better ways to maintain gradle installations on a mac like brew, gvm or the gradle wrapper. Another problem was the less and less interest in gradle macports support.