Rather, your MAD theology tells you to ignore Christ's words as inapplicable to you
Whatever his motivation/reasoning - it doesn't change what he said. Nor is this the only place where Paul confirms God's Law in his own life and in the Christian's life. Example:
Acts 21:20-26 When they heard this, they praised God. Then they said to Paul: “You see, brother, how many thousands of Jews have believed, and all of them are zealous for the law. 21 They have been informed that you teach all the Jews who live among the Gentiles to turn away from Moses, telling them not to circumcise their children or live according to our customs. 22 What shall we do? They will certainly hear that you have come, 23 so do what we tell you. There are four men with us who have made a vow. 24 Take these men, join in their purification rites and pay their expenses, so that they can have their heads shaved. Then everyone will know there is no truth in these reports about you, but that you yourself are living in obedience to the law. 25 As for the Gentile believers, we have written to them our decision that they should abstain from food sacrificed to idols, from blood, from the meat of strangled animals and from sexual immorality.” 26 The next day Paul took the men and purified himself along with them. Then he went to the temple to give notice of the date when the days of purification would end and the offering would be made for each of them.
We see here Paul's endorsement for the Mosaic Covenants in the life of the Jew, even under the New Covenant. These are still very much applicable.
Gentiles are treated differently here - neither Paul nor Peter endorse the idea that gentiles are required to embrace the Old Covenant and be physically circumcised (their heart must be however). Instead they direct them to follow the Noahide Covenant. This is not, however, because there is a different Gospel - both are saved by Christ under the same New Covenant. Rather, the reason is because the New Covenant does not invalidate God's previous Covenants.
Of course, the New Covenant is really an extension of the Abrahamic Covenant. Hence Paul says -
Galatians 3:16 The promises were spoken to Abraham and to his seed. Scripture does not say “and to seeds,” meaning many people, but “and to your seed,” meaning one person, who is Christ.
Galatians 3:29 If you belong to Christ, then you are Abraham’s seed, and heirs according to the promise.
So you see you are wrong to separate gentiles from Israel; the promises of the New Covenant, the promises of Christ's Gospel, are really the fulfillment of the Abrahamic Covenant. Israel is the natural recipient of these promises - while gentiles are as wild vines that have been grafted on and thereby become fellow heirs and partakers of God's promises.
Now, where does God's Law fit into the New Covenant you may ask? It is written on the believer's heart:
Jeremiah 31:31-34 “The days are coming,” declares the Lord, “when I will make a new covenant with the people of Israel
and with the people of Judah. 32 It will not be like the covenant
I made with their ancestors when I took them by the hand
to lead them out of Egypt, because they broke my covenant,
though I was a husband to[d] them,[e]” declares the Lord. 33 “This is the covenant I will make with the people of Israel after that time,” declares the Lord. “I will put my law in their minds and write it on their hearts. I will be their God, and they will be my people. 34 No longer will they teach their neighbor, or say to one another, ‘Know the Lord,’ because they will all know me, from the least of them to the greatest,” declares the Lord. “For I will forgive their wickedness and will remember their sins no more.”
Luke 22:20 In the same way, after the supper he took the cup, saying, “This cup is the new covenant in my blood, which is poured out for you.
2 Cor 3:4-6 Such confidence we have through Christ before God. 5 Not that we are competent in ourselves to claim anything for ourselves, but our competence comes from God. 6 He has made us competent as ministers of a new covenant—not of the letter but of the Spirit; for the letter kills, but the Spirit gives life.
So we see here, the New Covenant was promised to Israel, and it was promised to them because of God's Covenant with Abraham. Israel is Abrahams natural descendent and natural heir to the promises of God. However, if you belong to Christ, you are also considered to be of Abraham's seed; we are grafted onto Israel, the natural heir. Furthermore, under the New Covenant, we are told that God's Law will be written on our hearts. Obviously, then, God's Law is still very much important the believer - whether gentile or jew.
Paul says something interesting in another place that may help shed some light on the seeming contradiction between the above and the fact that neither Peter or Paul endorsed the idea of the gentiles getting circumcised and embracing the Mosaic Covenant.
1 Cor 9:19-23 Though I am free and belong to no one, I have made myself a slave to everyone, to win as many as possible. 20 To the Jews I became like a Jew, to win the Jews. To those under the law I became like one under the law (though I myself am not under the law), so as to win those under the law. 21 To those not having the law I became like one not having the law (though I am not free from God’s law but am under Christ’s law), so as to win those not having the law. 22 To the weak I became weak, to win the weak. I have become all things to all people so that by all possible means I might save some. 23 I do all this for the sake of the gospel, that I may share in its blessings.
See here: he distinguishes between the Mosaic Law and God's Law/Christ's Law! This is an important, but often missed distinction. This is expounded on a bit in Hebrews.
Hebrews 10:5-10 Therefore, when Christ came into the world, he said: “Sacrifice and offering you did not desire, but a body you prepared for me; 6 with burnt offerings and sin offerings you were not pleased. 7 Then I said, ‘Here I am—it is written about me in the scroll— I have come to do your will, my God.’”[a] 8 First he said, “Sacrifices and offerings, burnt offerings and sin offerings you did not desire, nor were you pleased with them”—though they were offered in accordance with the law. 9 Then he said, “Here I am, I have come to do your will.” He sets aside the first to establish the second. 10 And by that will, we have been made holy through the sacrifice of the body of Jesus Christ once for all.
The Mosaic Law was good and taught right from wrong, but if you approached it purely as a list of do's and dont's - you missed the Spirit of the Law. That is to say - you lacked an understanding of God's will for us. He allowed for many things under the law that he didn't like - such as divorce and sacrifice. He also didn't force people to live as saints under the law. But for one who pursued the truth and God's will, they would discover the Spirit of the Law - those underlying principles and values that God cares about, that we as Christians should live by.
Mind the difference between the Law and God's Law in Romans 7. Note what he says at the end:
Romans 7:21-25 So I find this law at work: Although I want to do good, evil is right there with me. 22 For in my inner being I delight in God’s law; 23 but I see another law at work in me, waging war against the law of my mind and making me a prisoner of the law of sin at work within me. 24 What a wretched man I am! Who will rescue me from this body that is subject to death? 25 Thanks be to God, who delivers me through Jesus Christ our Lord! So then, I myself in my mind am a slave to God’s law, but in my sinful nature[d] a slave to the law of sin.
Do you have God's Law written on your heart?
I agree with your assessment.
LA