It is somewhat true in regards to what you say but at the same time it isn't. VEGETA_DTX explained it best in his posts so I won't bother repeating what he said. I would like to add that, when it became a story of aliens and intergalactic travel the title was put under a new name, a new product, Dragonball Z.Toriyama has evolved & changed Dragon Ball's original point, style. Originally, it was a comedy-adventure-fantasy style series, with Goku & friends looking for Dragon Balls. Eventualy, it become more serious and became took an action-fighting-kill-the-evil-multitransforming-guy style. Originally, the art style was more rounded. Eventually, the characters became more squared. See?
That is true! The change becomes quite more noticeable after the invasions of the Saiyans. There was a cycle that was in Dragonball early on but it was much more consistent and drawn much better than opposed to later on.VEGETA_DTX wrote:I believe that the art style in Dragon Ball Z is varying much more on the per-episode basis than on per-saga basis
Episode 1 of DBZ compared to Episode 128:


Same art studio.

Same Saga. Pick, which one is better? Proportion, style?











