"It's a completely normal US trend."
It's not only "tech titans" and it's not an American "trend" or invention.
And while we may be experiencing a pandemic "baby bump" the overall birthdate is trending downward in America. And apparently the "trend" is for wealthy have less children these days. Also education is a huge factor. Highly educated parents seem to only have 2 children.
"As the income scale increases, the birth rate decreases, with families making 200,000 U.S. dollars or more per year having the lowest birth rate, at 43.92 births per 1,000 women. Income and high birth rates are strongly linked, not just in the United States, but around the world.Sep 30, 2022"
Contraception and family planning (or lack thereof) are the significant factors and one reason why poor families sometimes have too many babies but it is also due to the need for more help on farms, in rural areas and poor countries, etc.
And in history ...
It is estimated that Genghis Khan fathered around 1000 children.
Henry the 1st had 24 that we know of.
Charles II Had At Least 14 Illegitimate Children
Holy Roman Empress Maria Theresa Gave Birth To 16 Children
And many more examples exist of historical "trends".
So not an American invention or trend ... shall I say it? It's "tragic" some people don't seem to know how history power and sex works. :)