The question is not that there is anything wrong with the statement. But rather is it truly NEW. Is the idea that there needs to be a thing called New Covenant Theology valid when you consider that the idea that the Old Testament Law could be summed up by loving the Lord with all your heart and your neighbor as yourself was in ..... the Old Testament. There is nothing wrong with coming up with a concept that might appear to be overlooked and then maybe even writing a book or blog on it but is it a valid new theology or a "nothing burger"?
The "New Covenant" part of "New Covenant Theology" actually refers to the "New Covenant". It is more than obeying the Law of Christ
"Bear one another's burdens, and so fulfill the law of Christ." (Galatians 6:2)
It is the work of Christ and Christ Himself (hence the use of "Christocentric").
The Old Covenant looked to this:
Jeremiah 31:31–34 : Behold, days are coming,” declares the Lord, “when I will make a new covenant with the house of Israel and with the house of Judah,
32 not like the covenant which I made with their fathers in the day I took them by the hand to bring them out of the land of Egypt, My covenant which they broke, although I was a husband to them,” declares the Lord.
33 “But this is the covenant which I will make with the house of Israel after those days,” declares the Lord, “I will put My law within them and on their heart I will write it; and I will be their God, and they shall be My people.
34 “They will not teach again, each man his neighbor and each man his brother, saying, ‘Know the Lord,’ for they will all know Me, from the least of them to the greatest of them,” declares the Lord, “for I will forgive their iniquity, and their sin I will remember no more.”
Hebrews 8 But now He has obtained a more excellent ministry, by as much as He is also the mediator of a better covenant, which has been enacted on better promises.
Hebrews 13:20. Now the God of peace, who brought up from the dead the great Shepherd of the sheep through the blood of the eternal covenant, even Jesus our Lord,
Hebrews 13:20 is also the reason I do not believe Covenant Theology's "covenant of redemption" (the supposed covenant between the Father and Son) is the everlasting covenant. Scripture seems to at least indicate that Christ Himself is the Eternal Covenant.