Some theists claim that god created the universe.
Why would god be interested in creating anything?
Very strange question. God made everything perfect, and at one time the planet was able to sustain life. Now under the curse it just supports it for a short time.
God made man in his image, just like him. With that came free choice.
1 John 3:9 is also does not mean the way your reading it.
Little children, let no man deceive you:
he that doeth righteousness is righteous, even as he is righteous. He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil. Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God.
(1Jn 3:7-9)
The opposite of doing righteousness is doing unrighteousness or things not right with God. Righteousness just means right standing with. Someone that continues to do unrighteousness is not born of God.
AMP:
No one born (begotten) of God [deliberately, knowingly, and [8] habitually] practices sin, for God's nature abides in him [His principle of life, the divine sperm, remains permanently within him]; and he cannot practice sinning because he is born (begotten) of God.
(1Jn 3:9)