Should the laws of society be altered in the following way:
Anyone is allowed to cause harm to another as long as that harm is counterbalanced by something that is generally agreed to serve as sufficient compensation for that harm. e.g. Physical assault is now decriminalised in cases where the assailant gives some specified amount of financial compensation to the victim made on a case independent basis.
While it's often possible to sue someone for damages incurred as the result of their behavior, this is a civil matter and doesn't affect the criminal aspect of that damage. The person who commits the crime still has that charge count against their criminal record and may face jail time or similar. The proposal insists that no one should face criminal charges if they are able to compensate their victim.
The question immediately arises as to how the compensation should be determined. If procreation is accepted as legal, then one way might be to sum the total amount of good in a person's life and divide by the bad. For example, if you wanted to determine the compensation required for intentionally tripping someone over, you simply take the amount of damage that causes and multiply it by the ratio of average good to average bad in a person's life.
Because natalists often claim that the good of life outweighs the bad, I'll assume that they've already quantified the relative amounts of each and have those figures on hand to help calculate the compensation. My guess is if you were to actually compute these values, you would conclude that what people intuitively feel about how much compensation should be issued is much higher than the amount arrived at by this calculation. The implication of this is that either people should be permitted to inflict harm on others at little expense or that procreation inflicts more harm than is acceptable.