Gohan advances so much in this episode -
he makes his first human friends
he learns a valuable lesson about growing up
he learns what it is truly to be free, for the first time of his life
and he finally understands what he must do and that he holds great power, it would be a shame and waste it doing nothing.
As a watcher, after all gohan's struggles, you cheer for him and you want him to reunite with his family but throughout his journey, gohan learns so much than his time with his parents actually, he learns to survive, to find food on his own, he overcomes his fear of heights, he learns how to make friends, he learns a lesson about death and becoming mature and caring for other people.
By the end of this episode, gohan is ready both mind and soul to begin his training and it was well earned journey.