Nah, Goku slaps Author Inserts by an unquantifiable degree. Kid Goku fought Akira Toriyama, an author insert, and was comparable to him. Goku now is much stronger than Kid Goku, and by an unquantifiable degree.
Unquanitifiable means "impossible to express or measure in terms of quantity."
So Goku's growth, especially after the Frieza saga, can't even be expressed numerically. This explains why the x2 multiplier doesn't make sense for SSJ2, because we're trying to quantify increases in power that are unquantifiable due to the sheer strength of the characters transcending numbers entirely.
So, Goku is stronger than Tier 0s that surpass numerical concepts. And Chi-Chi and Bulma individually > Goku because Goku is afraid of them.