Marrying a divorcee automatically brings prudent suspicions along with it.

1. While my uncle did marry a divorced woman, that doesn't mean he wasn't validly married. Could be any number of reasons, including: Pauline/Petrine privilege, annulment of her previous marriage, or the previous spouse is now deceased. Terminology can be muddied in the modern world. Yes, sometimes people continue to identify as divorced even though they are not, or a widow, by Catholic thinking.

Yes, words have meaning. They have meaning for people outside the traditional movement, who may in some cases use these words in a different sense.

You brought up advising people. There can be circuмstances people don't know. Is it the layperson's job to function as marriage investigator?

Also recall the Pauline privilege and Petrine privilege.

I don't agree.
I think many marriages if not MOST marriages today are counterfeit, because people enter them thinking "if this does not work out I will get divorced, or with expectations of 2 children, home-ownership, a career for the wife, and a world cruise and early retirement.  Since the VAST majority of people enter marriage intending to use contraceptives, then the vast majority of marriages must be invalid, since a lack of openness to life invalidates a marriage and using contraceptives from day one demonstrates a clear intent.
I cannot speak for other cultures, but I certainly see a LOT of this in the UK.  Once a culture starts referring to people as "my partner", rather than my husband or my wife, then the formality of marriage is dead.  It's like acquiring a driving licence in Somalia.  Why bother?  Nobody else has one and even if you can drive you have to bribe the examiner assuming an examiner exists in the first place.
But this is not to say that the solution is to issue more annulments, but rather to refuse to marry people who cannot demonstrate and in fact articulate that understanding.  If the Church ever recovers and leads the world out of this mess I imagine it will need to have a marriage course where people are scrutinised before they are allowed to marry each other in Church.  Then one could reasonably apply tougher judicial standards to annulments.   But it would have to be a very different world than the one we live in for this to work.

I would have thought it was yes.  At least to the point of speaking up when they know a person has a dodgy marriage.
It is right there in the marriage service.
"If any person present knows of any lawful impediment to this marriage, he or she should declare it now"

So it is right there as an invitation or even a command.  And it would not be included if it was not a layperson's responsibility to speak up when they knew.

It happens in trad churches, too.
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