system
Given the following post, respond as if you're commenting on Reddit:
human
[Dragon Ball] Are the main cast so strong because they had extra lives?

I was just thinking, if dragon balls couldn't bring people back from the dead, there would be no way for there to be a super saiyans or golden forms. 

The main cast was also was exposed to parts of the macroverse no mortal would have access to and they were able to bring what they learned back with them when they came back to life.  Are the main cast so strong because they had extra lives?
gpt
In the sense that they were able to train with King Kai, yes, the extra lives made them stronger. Also in the sense that Vegeta coming back to life on Namek probably gave him a zenkai.

Think of the Z Warriors as nameless NPCs you control. You burn wishes/gold on bringing them back to life, and while it doesn't make them directly stronger, it gives them the ability to continue to become stronger. Cause you know, they're alive again.