[mattnewport]

That's not really accurate. Component based systems are designed specifically to address situations that traditional inheritance doesn't handle well.

Examples are usually something like having a base entity, a player that inherits from entity and an enemy that inherits from entity. Then you have a magic user and a barbarian inherit from enemy but now you also want your player to be able to use magic. Traditional OOP doesn't make it easy to share the implementation.

Even with composition and interfaces you still have problems with most traditional OOP languages when you want to do things like change the set of components of an entity dynamically at runtime (player gains or loses the ability to use magic during the game).

"Is a" is often not the relationship you want to model. A player and an NPC both have the "has a" relationship to an inventory, not the "is a" for example.