Also the reasoning
"We have always had this"
Isn't a valid reasoning for it to continue. ie slavery, women not having the right to voting, etc. Not trying to say this is that profound an issue but this argument irks me because it just isn't relevant that things were done like X before.
Beyond that it doesn't make much business sense.
And actually on android there is a separate marketplace for advlt content games with much less visibility. It would not be a wise business decision to have advlt content for the sake of advlt content.
Also your own flawed argument doesn't work for the content you described. Fallout hasn't had pregnant women or children fighting in their games so I don't know where that came from.
Now what I wouldn't mind seeing is suggestive text from dwellers who were previous partners in making a baby. Maybe them pondering out loud what their partner is up to, or asking if they want to make another baby. Perhaps even hinting at who they'd like to hook up with or gossiping about who is hooking up with who.
That'd be pretty dynamic and cool to see.