anonymous question

I can answer in one word: deregulation. But that is obvious to everyone, because deregulation awaits all institutions under ancap, so let’s fantasize about where it will lead and what forms the institution of marriage might take.

What functions of marriage do we have today?

1. Marriage is a subscription to sex. Since humans are generally inclined to save effort, this function of marriage will be preserved under ancap, regardless of how much ideological polyamorists dream otherwise. But a subscription, of course, will not imply exclusivity by default, just as it already does not. The word “infidelity” will finally become a thing of the past, alongside other archaic terms like “sacrilege” or “vendetta”.
2. Marriage is a form of organizing a household. Here, as people become wealthier, this function will increasingly wither away. Roughly speaking, the norm will be an autonomous household, with the possibility of visiting a partner from time to time or organizing a joint tour. Housekeeping itself will become even more automated, and whatever automation does not handle will be perfectly executed by specialized companies, like modern cleaning services.
3. Marriage is a form of friendship. The continuing improvement of communication channels will make framing friendship as marriage less and less relevant. People easily meet and grow close without such a status, regardless of gender, age, and increasingly even social standing. Ancap will only exacerbate this trend.
4. Marriage is a cooperative for raising children. To the same extent that the model of marriage as a form of friendship blurs under ancap, the model of marriage as an institution for upbringing will also blur. A child will have a much greater degree of freedom, including in the choice of friends, guardians, and teachers.
5. Marriage is a form of legal entity. In the absence of a state that provides the right of legal representation without a power of attorney only to family members, this model will also blur. People will formalize situational relationships of mutual trust using simple and cheap mechanisms, for example, based on blockchain. In the absence of such formalization, a counterparty will be forced to act regarding someone’s acquaintances at their own risk. However, the aforementioned development of communication will allow one to easily obtain all necessary confirmations if necessary.

So. It is quite likely that the form of marriage we know today as traditional will be preserved under ancap as a kind of archaism, however, the role of the institution will be noticeably reduced and replaced by clearer and more specific contractual relations between people.