I would appreciate it if you gave me a little bit more charity. Your constant insults are neither necessary or helpful. I am not insulting, even though I know you are in the mud and not nearly as informed about this subject as you would like to make pretense. Perhaps you would have an easier time if you ditched the attitude. Bear with me please, and with patience.
Nous does not mean "common sense and practical knowledge". Not in any context that I am aware of, and certainly not in the context of Orthodox theology. It is, as I said, the intellect as a whole, including not only the mind, but influences, priorities, pulls, passions, etc. It is like the eye of the heart and soul.
The Ultimate Reality means exactly what it means. You say it means "Objective reality, which of course exists".
Perhaps if you did not have all this baggage and superstition attached to the word "God", you would not struggle as much. But here, let me help a little more.
All definitions courtesy merriam-webster...
Entity - being, existence; especially : independent, separate, or self-contained existence
Being - the quality or state of having existence
Existence - the state or fact of having being especially independently of human consciousness and as contrasted with nonexistence
I hope this helps to reveal something to you. When I say, "God is The Supreme and Ultimate Reality", I am really talking about the truest, all encompassing, all pervading, uncircumventable, perfect, reality. Absolute existence.
Truly, reality itself, and in the truest sense of the word. In fact, to say there is no Ultimate reality is to deny reality and existence itself. As our very experience scientifically confirms, there is some form of existence, reality. If there is some form of Reality, there is an ultimate reality.
So I am sure even you can see, if you are willing, that God obviously exists, and it is self evident. Apodictic truth. Likewise, an entire tree of logic built off faulty premises will come to reasonable conclusions that are false. That being the case, in ones love of The Truth, calibrating the tool that is being used to measure and cleaning the lens of one's instrument is more integral than reason itself.
Because The Word of Truth itself said, "Blessed are the pure in heart, they will see God", not "Blessed is the one who is best at mental gymnastics, they will see God", neither "Blessed are those who are philosophically advanced and logical, they will see God."
A pure heart is a clean and undefiled nous.
And truly, even purifying the nous as the active process of abiding in The Way, The Truth, and The Life is an apodictic truth.