Catholics do not arrange our sex laws for maximum procreation. We forbid artificial contraception, not because we want the maximum number of children but because artificial contraception tries to thwart the procreative purpose of sex while still grasping the pleasure connected with it.
We don’t “arrange our sex laws for maximum procreation”. Catholics are free to practice NFP. Furthermore, our “sex laws” are not a “biological proof” of anything.
True, Christ, and by extension His Church exists for the salvation of all (maximum amount of) souls.
Christ arranged commandments and teaches us through the Church what is sinful, and so in a way the commandments are laws.
Marriage’s purpose is procreation, but that procreation is according to God’s will, and may be one child, or 15.
The maximum is what God wills. You are permitted to abstain from sex in a marriage, especially to space out births and so forth, as long as your heart is open to God’s will for children.
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