The problem though is that in the United States the baptist movement was fueled by the progressive temperance movement. Prior to the Civil War there were very few baptists in the United States. In fact, anabaptism had been largely stamped out all over the world. After the Civil War the progressive movement began and rejected anything historic. This extended into the church, in fact in many ways the progressive movement was a product of the church.
It should come as no surprise that the baptist movement began in the south and to this day is still centered in the south. During the Civil War both the north and the south were convinced God was on their side. Obviously the south lost, losses were horrific on both sides but worse in the south. The despondency associated with losing caused a shift in the south from historic churches, largely calvinistic, to something that completely rejected the historic churches that had led the south to lose the war. The baptist movement offered people an anti-historic church and it offered people a better life through law.
I don’t think people appreciate just how much the civil war negatively affected the church in this country. It is from that war that the progressive movement in both the north and the south flow. The south outright rejected the historic church, which was easy to do because the historic church said God was on the side of the south and the south lost. In the north, the carnage of the war didn’t cause people to leave the church but it did cause them to seek its fundamental change. Within two generations the mainline southern churches didn’t exist or otherwise became baptist. In the north the mainline churches remained in name but they utterly rejected historic Christian theology. The nation has never recovered.
In EVERY war; each side is convinced of this!
What you are doing in your lengthy theory is using the rejection of some true historical Biblical truths to justify a perpetuated tradition (you likely also support NT ministers distinctively titled priests) that was reject by churches which held to historical Biblical truths.
The SBC affirms the latter but rejects infant baptism, as paedobaptism is not what Scripture most plainly teaches but was a tradition which developed at time went on. Again, unlike circumcision, the Biblical requirements for baptism require repentance and faith, and which infant are incapable of.
Nor does the act of baptism make one a believer unless one can believe. God has no grandchildren as no one is saved by proxy. Period.