Just to be clear, do you believe that Paul is calling holy days that the almighty eternal God created, such as the day of atonement, "weak and beggarly elements"?
Paul was addressing two groups in Galatians, the false teachers who were formerly Jewish and the converted, formerly pagan Galatians. As it would be blasphemy, both for anyone and for Paul to call God's ordained holy days anything like weak and beggarly, and since verse 3, chapter 4, mentions the elements of the world, it is clear that the elements of the world, not God is what he is addressing, or pagan beliefs.
There are a couple of problems with this (thus some of the debates you might see on this thread, etc.) But, in my view, one of simplest objections to the 'law is a curse' argument, is just that through book after book of the Bible, no one seems to suggest it is impossible to keep, although many of the Prophets point out that there is a lot more to keeping the law than outward observances.
Some would argue that the Old Testament is abrogated by the New, but even in the New Testament we read of: 'a certain priest named Zacharias ... and his wife ... and they were both righteous before God, walking in all the commandments and ordinances of the Lord, blameless.' (Luke 1,5-6)
A standard theological response to these questions is given by John Calvin who says:
When [God] calls it a perpetual or eternal covenant, the Jews rest on it as a ground of their obstinacy, and wantonly rave against Christ as a covenant-breaker, because He abrogated the Sabbath.... Whatever was spoken of under the Law as eternal, I maintain to have had reference to the new state of things which came to pass at the coming of Christ; and thus the eternity of the Law must not be extended beyond the fulness of time, when the truth of its shadows was manifested, and Gods covenant assumed a different form. If the Jews cry out that what is perpetual, and what is temporary, are contraries to each other, we must deny it in various respects, since assuredly what was peculiar to the Law could not continue to exist beyond the day of Jesus Christ.