The significance of there being no significant law against the goods associated with the fruit of the Spirit is that if there were one, everyone would always have at least one untrumpable reason for breaking that law and, consequently, rejecting Christianity. God in His perfect wisdom knows that and so He would never make Christianity genuinely foolish. How does this work? Well, if Paul tells us that Christians, operating under the influence of the Holy Spirit, naturally yield love, joy, peace, patience, kindness, goodness, faithfulness and self control and there just so happens to be a law against such things, a law that trumps our desire to do such things, then we have a good reason to act contrary to the law that God has written on our hearts by dint of the Holy Spirit. And if this were the case, then the gospel genuinely would be foolishness. (Of course, it’s not really foolishness.) No one (wisely) puts their ultimate interests at maximal risk by violating laws that they could rightly be held accountable for violating.
This is the difference between being under an external law and being under an internal law. To be under an external law is to be judged by that law. It is to have to answer for our violations of such a law. However, to be under an internal law is different. It is to be motivated by such a law; it is to want to live in accordance with such a law; it is nothing more than to want to do what comes naturally when you are not sowing to the flesh. And being under and internal law does not entail that we will be judged by the internal law, externally. That is, just because God gives us His Spirit, changing our desires, does not entail that He is going to judge us by how well we conformed to this law, for that would be no different that being under an external law with vague demands. This is not the gospel!! For we are not under law but under grace (i.e., unmerited favor–Romans 4:4). We have every motivation to live in accordance with the Spirit of God and to produce fruit for His Kingdom except one, namely, that we will be judged for falling short of this internal law (at least with respect to salvation). That is the bond woman that we must cast out!