> Sexual unfulfillment is, I believe, one of the largest driving factors behind a lot of cheating and divorce.

Maybe, but I don't think it's a root cause in most cases. Like, even if you had a social framework in place for the high libido partner to receive fulfillment outside the relationship, the issues (misaligned expectations, boundary issues, money stress, contempt, etc) that led to the breakdown in intimacy would still remain and and end manifesting in other ways.

I think probably a more helpful direction is to provide more guidance to couples for how to communicate around intimacy, how respond effective to a coalmine canary issue like "the sex isn't very good any more" in a way that uncovers the root causes rather than blaming one person for the symptom ("it's the LLP's fault for not doing the thing") or trying to fix it with band-aids ("just have more date nights lol").

You make a lot of assumptions here. Sometimes the answer is simple and people are not sexually compatible, were never good at having sex together and rushed into a long term relationship. I've seen this more in people who were further along the 'sexual repression' spectrum (i.e. following religious advice about relationships and marriage).

Sometimes I think cheating and divorce is as much the norm as mating for life. I was reading a study recently that found that sexual intimacy steadily decreases over time in a long term relationship, and only seemed to go back up again if divorce/new partner happened. I will dig it out if anyone is interested.

There is a taboo around non-monogamy which I think is detrimental to many people, and certainly a lot of people make multiple partners work, despite all the barriers to doing this in most societies. It isn't a sticking plaster for other issues, that I agree though. If anything it needs the participants to understand well what they want and to be excellent communicators - something we can probably all work on.

The opposite could easily be argued, that holding onto taboo is what makes it difficult for victims to seek help and what allows predators to act unabated.

The most sexually repressive societies have some of the worst sexual sociopathic behaviour, I don't think I need to give examples.

Those preaching sexual liberation were the ones who fought and won the battle to incorporate homosexuality into our social norms.

No. In fact it turned out that gay people wanted to be like straight people. They wanted weddings, marriage, the ability to hold hands in public, to adopt children and so on. They didn't want "sexual liberation," they wanted their relationships to be accepted the same way hetereosexual relationships are.

Being gay or accepting such was a part of being "sexually liberated" back then. Just as being into kinks is a part of being "sexually liberated" now. I don't understand why you insist on conflating it all to marriage and children (or lack thereof).