Paul is setting up a pretty false dichotomy here. He's essentially saying that unmarried religious people are more devoted and less distracted and that the opposite is true for wed folks. This is clearly not the case. Both groups are obviously concerned with worldly things as we need them to live. Likewise as I've said, virgins are going to be more distracted by their sexual energies. Women especially are prone to becoming depressed at a certain time when they become older and have no children, they start desperately wanting children. This can lead to all sorts of horrible outcomes. Men may act out violently or in unconventional ways. They may masturbate in secret or even do it in their sleep as women may do. Without partners people become depressed. Nothing can replace sexual-romantic love and having children. G-d made us this way and it's not a mistake or a personal failing. It's not that a certain few can live without these things and spend their whole lives in religious ivory towers - it's that they shouldn't have to, are not commanded to and will gain no benefit from this unnecessarily cruel lifestyle whatsoever. They can be just as close to The Eternal were they married, if not closer as they are happier, satisfied, likely have children and someone to love. This is how G-d made it.
Jewish males are also commanded to have at least two children, a boy and a girl.
Tehillah 127 says,
Lo, children are an heritage of the Lord: and the fruit of the womb is his reward.
As arrows are in the hand of a mighty man; so are children of the youth.
Happy is the man that hath his quiver full of them: they shall not be ashamed, but they shall speak with the enemies in the gate.
Paul (his Roman name) was Saul, a former Pharisee, educated at the feet of Gamaliel....he knew the law better than most. He was zealous for the Law his whole life and he persecuted the Christians as a duty to his God.
After an encounter with Jesus on the road to Damascus, Paul came to know that Jesus was the Messiah. He was confident from his knowledge of the scriptures that Messiah would set up his kingdom on earth. All of his Jewish disciples felt that it was immanent....The apostles asked him as he was ascending to heaven if he was going to establish his kingdom there and then? (Acts 1:6) No one knew when the kingdom was going to be established, because God had not told anyone....not even Jesus. (Matthew 23:36-39)
So, since they believed that the kingdom’s coming was immanent, the work that was assigned by Jesus was viewed as urgent.....lives were at stake. This is what motivated Paul to recommend singleness.....not that he had anything against marriage or sex, but because the work needed their full attention.