I was one of your downvoters. I can explain why I downvoted that answer. (Italics and bolding mine, for clarity lest you misread.)
First, it was (to my reading) very negative and opinionated. My experience on a number of SE sites is that good answers are more dispassionate and supportable. Good answers are useful. They address the OP's concern.
You start right off by disparaging the other answers:
Most set phrases that relate to this are very wrong answers.
If everyone was so wrong, the other answers (which were reasonable, supported with links and might actually help the OP) should not have gotten support. You are implying they did so because we are not as insightful as you are (which does fly in meta, but not on the main site).
Meal ticket (a good answer) is reduced to gold digger, which you informed us was akin to a crime. Sure, we don't respect them, but is all this necessary? It sounds so squalid.
A gold digger refers to a young, hot girl who finds an older, rich man who marries her or provides for her. This is a disparaging term to refer to a delinquent lifestyle. The male in this case is a sugar daddy. Similarly disparaging, and often he is married to someone else and having an affair.
Then you opine that "marry a guy and he'll provide" is
a token of wisdom and tradition, describing the way society works.
You inform us of how American society really works, which is why everyone who answered is presumably wrong (and kind of refute yourself in the process):
Since American society does not think of marriage this way (is there only one way to think of marriage in all of American society?), there will be no such idiom. American society reveres marriage out of love and disparages marriage out of convenience. Americans view this as a necessary evil and something to avoid acknowledging and thinking about as much as possible.
This is a helpful answer? To whom? Is it supportable? Is it about the English language?
I don't speak for everyone here (nor you for all of American society.) But when someone wants to express an opinion, that's what comments are for.
Downvotes are part of the reality of SE. It is always amazing to me that people make such a fuss over them. I can't begin to count the number of downvotes I've gotten (well, technically I probably can. Just let me say I've gotten plenty.) If I don't want them, I'm careful to try to give helpful answers; that's the best I can do. If I've done that, it just doesn't matter if someone doesn't like my answer.
Now, if no one ever upvoted me, I'd have to rethink my answers pretty seriously.