AI doesn't work nearly as well as you seem to think it does. For something as excruciatingly difficult as a space mission, humans have proven to be well up to the task. The headline of this article here is one illustrative data point.

Furthermore, many methods that are currently classified as "AI" act because of very complex and often opaque emergent behavior, and we often have a hard time (or don't know at all) why a CNN for example behaves as it does, or even how exactly it behaves. Do you want something that you neither understand nor can predict to perform a crucial job in your space mission?