Oh, it sounds plausible to me, but it seems to me it would take deep involvement to have a profound effect.
And on top of that, some people might just be born more sensitive to such things.
How would it be ethically researched would be a major question to me. Reviewing cases after the fact might be the only acceptable method, but that leaves open the hypothesis that those predisposed to mature faster might also “send precocious signals” when younger too.
Kinsey actually carried out evil experiments in the name of science, and came up with claims so weird that they can’t be considered research with integrity in any case.
All your points are accurate, and you’re right that no decent people would conduct experiments with sufficient controls to give clear data. At this point, it’s a hypothesis supported by some data.
One point that has been made is that the very young girls, 9 or 10 years old, whose pregnancies get public attention have all been victims of long-term abuse.