Is there a difference in how creative credit is typically assigned to a comic artist versus a mangaka?

Yes, there's a significant difference. In Western comics, credit is typically itemized, listing separate individuals for writing, penciling, inking, coloring, and lettering. The 'artist' usually refers specifically to the penciller or the penciller/inker team. For manga, the 'mangaka' is almost always credited as the singular creator of both the story and the art, even if they employ multiple assistants. This reflects the Japanese industry's emphasis on the mangaka's individual vision and comprehensive creative control over the entire work.