I don't know what your understanding of the statement of this scripture, but to clarify, the book of Galatians was the Apostle Paul's letter to the churches he had previously planted in Galatia, converting those who had been practicing paganism. Paul wrote to them because he had received word of a lot of confusion in those churches and that, evidently, some type of influence had crept in attempting to convert the Galatian churches back to Mosiac law, or Old Testament legalism, if you will.
In 3:28 and preceding verses, Paul is reminding them that under the New Covenant, "salvation" is earned by faith, not works as was the Mosiac Law. Specifically in 3:28, Paul is saying that for those who accept Christ's blood sacrifice death and resurrection, those who are born again as Christ described, under Christ's New Covenant there is no spiritual superiority of any group (gender, nationality, etc) over another...all are spiritually equal to each other in Christ Jesus.
I don't see the scripture's relevance to the topic.