This ruins the child
This is the problem with all these "marriage is best for the children" pieces that get published. They don't (can't?) look at situations that show what would happen if their agenda, to force people to stay married, was actually carried out. They can only see that a stable household under existing conditions has good outcomes. That's hardly a surprise. The question is whether a child in an unstable household gets a better outcome with that specific household staying together 'for the children', and my guess there would be no.
I know some successful 'ruined' children who would probably take issue with your summation there too.
But also even if we allow that there is benefit in a stable, two-parent household in which the parents don't change around at all, if we can even isolate that variable away from other factors, it seems tautological.
To make an analogy that's close to my heart right now -
In a drinking water capture system, you can probably collect the most water in a pristine, well-designed system where all the pipe gauges are the same and the fixtures are all well fitting and designed for the duty they perform. But if you haven't got one of those, if the one you have is full of holes and leaking all over the place every time it rains, and the pipes are jammed onto each other with no consideration of size or gaps, then ramming bits of cork into the leaks and praying isn't going to make it perform as if it was. Sometimes you're going to get better results if you rip out the downpipes, dig up the junctions and fit major parts of the system again.
Sure, it still might not be quite as good as that well-designed, perfect system, and you're probably going to get PVA glue all over your hands and clothes while you do the work, but it'll be a darn sight better than watching your drinking water piss out all over the veranda every time it rains...
I'm not sure if this comment is about divorce any more. Right, I'm off to buy more pipe fittings, grrr mumble mumble.
Who can do this? Who can possibly guarantee anything about the future, especially when it involves other people?
In the US at least, being raise by a single parent is a massive statistical indicator for basically every negative social outcome. Poverty, criminality, future generational single parenthood, etc.
Aside from that my anecdote is no less scientific than your conjecture. Correlation is not causation, it is far more likely that this statistical indicator comes from a third variable, say poverty.
USA has a abysmal social safety network. Single parents are left to fend for them selves, without protections in the workplace (meaning they can loose their jobs), without child sick leave, without financial support, with unavailable and unaffordable child care, etc. etc. Of course a kid raised under these conditions is gonna be statistically more likely to correlate with other negative outcome.
PS. I’m slightly insulted you unapologetically put future generational single parenthood in the category of negative social outcome. As if you’ve already concluded that it is bad.