Coffee has very similar processing to chocolate, can produce similar flavours with the right amount of roasting, but is not even close to the same thing due to the dramatically different fat content (both quantity and type of fat).
There’s a reason chocolate that has other plant fats blended into it is considered a highly inferior product to chocolate containing only cocoa butter, cocoa solids, sugar, and (optionally) milk. Cocoa butter’s melting temperature is just right for producing the intense, mouth-coating sensation of a good chocolate. Not to mention that cocoa butter carries much of the aroma compounds we love from chocolate.
There’s a reason chocolate that has other plant fats blended into it is considered a highly inferior product to chocolate containing only cocoa butter, cocoa solids, sugar, and (optionally) milk. Cocoa butter’s melting temperature is just right for producing the intense, mouth-coating sensation of a good chocolate. Not to mention that cocoa butter carries much of the aroma compounds we love from chocolate.