He actually offered to do so, but it was as a part of his single most common legal tactic - delaying. Basically he waited until it was functionally too late, then offered a sample if and only if the pages of the DNA report from the dress that had been held from his lawyers were provided in exchange. The judge refused to let this happen, because it would be opening a new line of inquiry set to make the case take even longer (which was the point).

Had the judge allowed Trump to submit the sample, and had he been allowed to continue to drag every step of that process out to the last minute (which is his standard MO in legal disputes) the election would have happened before the case was resolved and much like him being sentenced to "never mind, we good bro" for his 34 felony convictions this would have been derailed and dismissed, or SCOTUS would have rendered it invalid because our current SCOTUS serves Heritage first, Trump second, and the law in a distant third.

No, it is not, and it’s revolting to me that you’d think that. More than 3000 suits were filed in 1 year under the Adult Survivors Act, are all those “happy little accidents”, or do those people mean nothing and you only care about that one case?

Do you think the same identical law would have been passed if Carroll had never accused Trump? Lots of other people benefited, that is to be sure, but the specifics of when the law was passed and exactly what it did were entirely about creating a legal ability for Carroll to sue Trump that could reasonably be resolved before the election.

For example, the ASA discards statutes of limitations entirely for the window, rather than applying the new limit to old cases, because if it had only allowed applying the 20 year limit to old cases then Carroll's case would have been outside the scope even when she first made the accusation publicly. Out of the 3000 cases, I wonder how many involved conduct that happened prior to 2002?

This was not retroactive, however, so the ASA was passed to allow alleged victims to bring up their cases.

It wasn't retroactive because several state courts have found that changing a statute of limitations retroactively to apply to cases that were already outside the previous statute of limitations is an unconstitutional ex post facto law. If the statute of limitations is 3 years and you change it to 20, it cannot apply to any case already more than three years old without opening yourself up to another suit like Stogner v. California. The notion is pretty basic - you generally can't create a law that puts someone in jeopardy who was not already potentially in jeopardy for that conduct.

This is why the ASA is a separate law and why it only opened a temporary and narrow window for such cases. Such "revival" laws tend to do better in state supreme courts than a full retroactive extension of statutes of limitations.