Some fans have been underwhelmed by the explanation of how Han Solo and Chewbacca met in Solo: A Star Wars Story, while the official art book for the movie reveals a different version that inverts their traditional relationship.
In the Expanded Universe/”Legends” line, the relationship between Chewbacca (played in this movie by Joonas Suotamo) and Han (Alden Ehrenreich) was defined by a “life debt”―Han had saved Chewbacca’s life, and by the Wookie code of honor Chewbacca was now his servant. Though these original stories are no longer canon, the Disney continuity re-establishes this with the novel Aftermath: Life Debt, so fans expected to see Han save Chewbacca when they met in the new movie.
In the film (spoilers), Han, initially an infantryman in the Empire, has ticked off his superiors and is thrown into a pit to be fed to a “beast”―Chewbacca. Han talks to him, and convinces him that they can help each other escape. Whether or not this is supposed to be the beginning of their life debt remains to be seen, but many fans found it underwhelming compared to the old story, where Han had won Chewbacca’s loyalty by saving him in a more direct, difficult-to-repay manner.
What is interesting is that in the original concepts for the movie, as revealed in The Art of Solo: A Star Wars Story, their relationship was going to begin with Chewbacca saving Han’s life, not the other way around. In this version, the two were going to meet while fighting against the Empire in a sequence akin to World War I trench warfare. There, Chewbacca would push Han out of the way of enemy fire. The two would continue to save each other throughout the movie, establishing a more complex dynamic where both were essentially beholden to the other.
It would have been an interesting twist, and one which would have established the two on more equal footing―which admittedly could have made explaining their usual relationship somewhat difficult. It seems as if most fans would have preferred it to the Solo explanation, at least, which apparently tried to keep the original concept without being as exciting or sensible.
Whatever the case, it is possible that future stories will provide another cause of the life debt or expand on their relationship in other ways.