What gets left out is the fact that phytoestrogens are ubiquitous, found in many plant foods. [0]
The argument from the less concerned was something along: Better safe then sorry, no one can say what larger amounts of estrogen will do to a boy well below 1.
Saying “no one can say” means they literally have no idea. It’s not all that different than the statement “no one can say that 5G doesn’t cause cancer”.
Note that phytoestrogens are categorically not human estrogen, they are simply compounds that mimic some of estrogen’s properties.
Also of note: breast milk contains estrogen.
You might be right about “overly cautious” but I think doctors being that way is more reputable than gym rats quoting their favorite fitness blog.
We also took insane child mortality numbers and all kinds of defects for granted.
Our mothers still consumed food that has a tendency to contain/grow listeria. Then it was found in several cases where the reason for the death of the child was not known.
Now pregnant women (at least in Europe) are strongly advised to avoid products from raw milk and uncooked meat (hams and salami.
Things change, and not without a reason.
I’m not advocating blind adherence to tradition, I’m simply stating that the Null hypothesis is that soy foods are perfectly fine for health, until actual scientific evidence proves otherwise. All that exists not amounts to nothing more than conjecture, which, given the amount of attention this topic has gotten over the years, one would presume more evidence would be present by now.