Classical Theism is one of the main forms of monotheism, and dominant in at least Christianity. It says that God has aseity and also is immanent, transcendent, simple, immutable, impassable, and timeless. But these attributes are not just seen as being true independently, they arise from aseity. Chow explains:
The fundamental premise of classical theology is that God is the absolute source of everything that exists and is dependent on absolutely nothing for his own existence and nature. I will follow Plantinga in calling this the “sovereignty-aseity intuition.”
Chow, Dawn Eschenauer. Analogical Models of God: An Account of Religious Language. p79
In my readings it appears that Classical Theism is in turn dependent on realism, most notably in its explanation of simplicity: God's aseity means that God cannot depend on anything else. Realism would mean that, for example, goodness exists by itself, and so God cannot depend on goodness, and he does not then have an attribute of goodness. Instead concepts and attributes like goodness are equivalent to God's own essence (as is often said, the being of God is identical to the "attributes" of God), and any more complex attributes of God, like those that appear to be in tension like his justice and mercy, are only analogies.
My question is whether this philosophical realism is so integral to Classical Theism that anyone who is a conceptualist or a nominalist could not be considered a Classical Theist? Or if someone maintains all of the doctrines of Classical Theism but supports them through a philosophical foundation not based on realism, can they still be called a Classical Theist? In order to make this question not opinion based, answers could refer to when the label "Classical Theism" was coined and defined and what exactly its originators thought it entailed.