Here we have a couple problems: (1) how do we know who the father is? (2) how can avoid diluting the gene pool?
Solution (discovered thousands of years ago): monogamy, made publicly explicit through marriage ceremonies and enforced via shaming or persecuting fornicators, adulterers, and exalting as virtues both chastity and temperance
But no, in the modern Religion of Progress, it's sacrilege to deny the individual autonomy to do literally whatever they want.
Just another example of the possible consequences when you start pathologizing age-old Lindy values, tenets, customs, systems, etc.