Good analysis.
A little reading about the Alice in Wonderland nature of modern Physics helps to understand that our gooey brains don't create our consciousness, self, soul. It's the other way round. The idea of God as an old bearded man on a throne has its downside. When that is shattered for kids brought up on it in a church, or who receive ill treatment at the hands of elder "Christians" they trust, some will give up entirely.
Well, granted you’re starting with a billion more Christians than Jews (if you count Catholics, hehe...,) many of the notable (with an internet presence) counter-missionary rabbis claim hundreds of calls or emails per day from would-be former Christians. And there are growing communities in Texas and Israel of “Children of Noah,” Torah-believing non-Jews who believe in the G-d of the eternal Torah.
I cannot say if they tend toward large families like Orthodox Jews, so Christians have the demographic advantage for now. But it reminds me of a joke:
The Kinneset is debating their budget shortfall. “I know—” said a senior member. “After WW2 the Americans rebuilt Japan and Germany. Let’s just go to war with them and they’ll rebuild us after!” Asked another senior member, “One problem— What if we win?” ;)
It has to happen. It’s in the book.
It is a logical fallacy to point to People as proof of an idea. It the appeal to authority; some famous people left the faith, so it is not true.
Nancy Pelosi and Joe Biden are Catholics, so it must be true.
My view is to celebrate their conversion, lament their fall from faith, and hope they will find their way back to it.