When you talked about divorce I read divorce and I think divorce and not annulment. They are not the same thing.
I have heard it said, only on CathInfo and nowhere else, that the Church requires a civil divorce, before considering annulment. Maybe that goes for the "American church", but I find it hard to believe that the Holy Roman Catholic Church requires that all men who have annulments must first go to the state to get a divorce.
Maybe you can show evidence for such requirement.
Without looking it up, I can only guess that even if there is no such requirement in canon law --- which applies to the entire world --- it is some procedural "thing" in the American church. I would say it is probably to prevent any claims of "alienation of affection" under "heartbalm" laws, where those laws still exist --- you know how litigious Americans are. But that still doesn't address the question of civilly but invalidly married couples being told by the Church that their marriage is invalid. Maybe that is why the Church, so far as I am aware, always tries to help couples find some way to regularize their existing civil marriage,
not to suggest
"hey, you got yourself into this mess of an invalid marriage, you want to be a faithful Catholic, this guy/gal's not helping you and won't help you, in fact, he/she's a hindrance to you, why not make it easy on yourself, get free, get out of this s***show of a concubinage, and find yourself a Catholic mate who will actually help you get to heaven, instead of the alternative?". I've never heard of such a suggestion being made, though my "think outside the box" tendencies have led me to wonder exactly why. Some invalidly "married" couples
shouldn't try to "regularize" things and drive the nail in even deeper.
All I can say is, when I met with the DRE of my canonical parish (I am not a sedevacantist and I acknowledge that diocesan bishops still possess ordinary jurisdiction and authority, though they often abuse it), one of the first things I was asked for, was a copy of my civil divorce papers. The questionnaire doesn't even have a space marked "I don't have that yet". For many reasons, I never followed through.