Speaking personally, and perhaps it is indeed my conditioning, but at 25+ years of marriage I am living that beauty in 1 every day and I know without a doubt it has led me to my best possible life.
If the default happens to work for you, that's awesome, and in fact it's probably what will work for most people - otherwise it wouldn't be the default.
I'm just against considering alternative ways of finding happiness or purpose as consolation prizes, bittersweet stories, or somehow less valuable or beautiful than others. There's effort in keeping a marriage working for decades; there's also effort in daring to leave an unhappy comfort zone to find better ways, or simply to learn to live life in your own terms if "the one" never appears for you.
Everyone is winging it, and the only beauty is in finding happiness while causing the least harm to others (imho). Do the best you can with the information you have, maybe it works out, maybe it doesn’t.
I think that all four options are definitely possible, but that people have a bias for maintaining their circle of comfort, and justify that fear of the unknown.
As for
>You cannot deny that there's beauty in 1
I do deny it; or to be clear, I think it is a story that we've been conditioned to prefer over the others, with sometimes disastrous results for everyone involved. I see the same beauty in any other option that ends up with a person living a great life they don't regret.
I think we'd have a better world if people focused on finding their best possible life without a notion that this choice is the default, more likely option for a live well lived.