By "getting the shaft," nobody means getting rid of him altogether. They mean sit him on the bench while other characters actually do something significant and get the spotlight.
Then that's not getting the shaft, and them "getting something significant" often just meant treading water. If the lead character constantly needs to be removed from the story for your other characters to get focus, you're doing it wrong. In the Saiyan arc, Goku wasn't taken out of the story, he was dead, but still very much in focus along with other characters. Then in the Freeza arc, after taking a beating from Vegeta, he's traveling to Namek most of the early arc. That was organic, and the other characters made meaningful contributions to the story. However, taking Goku out of the fight became way too formulaic. It is in literally EVERY arc in DBZ. Sometimes it's organic, much of the time it's not and just is meant to keep the story going instead of pushing it forward. The rest of the time, very little comes of him being absent from the story. The formula is used TWICE in the Freeza arc. The first time when Goku's traveling to Namek and the second while he's healing from his fight against Ginyu. Both times it's used to create more drama, much like Justice League stories sometimes take out Superman in order to create drama given he's the most powerful member of the team. However, if you use it too many times, it grows tiresome as it did in the Freeza fight. When Goku is absent, the other fighters do no lasting damage or much of anything meaningful beyond get Freeza to reach his final form.
I don't like reluctant heroes. It's like, if they don't want to be here and they're the one on the adventure why would I want to be there watching or reading about them complaining, whining, or angsting? It's a huge turn off that's kept me away from franchises that employ it.
The trope works in certain places like Han Solo, but he has an arc. It gets tiresome in the Mad Max series because every single damn time he's reluctant to help and then ends up helping. That's not growth. I'd much rather watch either someone have an arc like Han, or want to help out.
It's fine for a character to have something cause them to question things
I'm the same. Every once and a while, it's fine to have a character question why they are doing things because perhaps their mission has taken a toll, but i think they should ultimately come around and reafirm why they do what they do.
What're you talking about? Goku does the same thing, but instead, he even gets more powers outta nowhere, while for Gohan, there was a bit of buildup.
Goku's potential only comes out once if you don't count Super Saiyan. His potential is fully tapped when he drinks the Karin's super spirit water in order to fight Piccolo, but at least there he goes through hell in order to get that power released. Same with Super Saiyan and the power he gained from healing after the Ginyu battle. Gohan is often not built up beyond "you have untapped potential." Piccolo helps Gohan reach his potential, then The Grand Elder magically brings up Gohan's full potential, then Gohan goes Super Saiyan 2 because he somehow has more untapped potential, and then the Elder Kaioshin brings out Gohan's potential and past that with his magic spell. Goku typically works for his or goes through hell to get it.
I don't think the first three sagas of DBZ focused on Goku's habits as much as the Buu saga and most of Toei's movies
You don't think the Saiyan arc focused a lot on Goku?
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