It wouldn't make any sense within the context of the surrounding verses to translate "telos" as "end", though even "end" as within it range of meanings "intention" or "aim". The point being made in the preceding verses that they misunderstood the point of the law, so pursuing the law as a means of establishing our own righteousness has always been a misunderstanding of it, which Paul spent a lot of time trying to correct and show that we have always been justified by faith apart from the Law. I recommend this article that talks about how this verse has historically been translated:
How is Christ the
In Deuteronomy 6:20-25, obeying the Law is in regard to having faith in God to free them slavery and to bring them up out of Egypt with a mighty hand, faith in God to defeat Pharaoh, faith in God to bring them to the land that He promises their forefathers, faith in God that His commands are for their own good, and faith in God to preserve them. So it is by faith that righteousness is theirs and by the same faith that they are to be careful to obey all of God's commands.
Indeed, as a Pharisee, Paul had though that righteousness came through observing the Law, and though he had zeal for God, it was not according to knowledge because he had been ignorant of the righteousness of God and had sought to establish his own (Romans 10:2-3). So righteousness apart from the Law hadn't been known to him, but now it had been made known.
God's Law is straightforwardly His instructions for how to live for Him. Are you seriously trying to argue that it is better to completely live in disobedience to God's commands than to try to obey them by faith and fail to do so faultlessly? All throughout the OT God wanted His people to repent and turn back to obedience to His commands, but now in the NT God wants His people to disobey them? Satan doesn't need to bother those who are living in sin, but those who are seeking to follow God.
The Law was never about how to become righteous, but about what we are to do because we have been made righteous. For instance, the Law reveals that it is acting in accordance with God's righteousness to help the poor, but no amount of helping the poor will ever cause someone who is not righteous to become righteous, but rather we are to help the poor because God has made us righteous. When we seek to do good in obedience to God's commands, the law of sin will stir up sinful passions, but that does not mean that we should not seek to obey God's commands.