Isn't that true for many if not most laws? We don't not have taxes just because lots of people will argue they're too high or too low, we don't not have a criminal justice system because people will argue sentences are too harsh or too lenient.
Instead, for things deemed worth having as law, we try to set the rules at levels that as many people as possible find as reasonable as possible (albeit in an imperfect way because there's indeed no way to get universal agreement on anything, and because not everyone acts in good faith when choosing, and because money influences politics too much, and all the other reasons why democracy is the worst form of government except for all the others).
Instead, for things deemed worth having as law, we try to set the rules at levels that as many people as possible find as reasonable as possible (albeit in an imperfect way because there's indeed no way to get universal agreement on anything, and because not everyone acts in good faith when choosing, and because money influences politics too much, and all the other reasons why democracy is the worst form of government except for all the others).