Nobody disputes that Jerusalem was the headquarters of the Church at the time of the council in Acts 15. The claim is a red herring.
This paragraph is just plain nutty:
It was not until the early 300’s the church stopped hiding underground from persecution and became a legal entity that the power was shifted to pagan Rome, specifically under Constantine the conqueror. The Pope became like the Caesars before him in Rome, only now with a Christian veneer. First there was little influence, but the doors slowly swung open to allow the pagans to enter the church through water baptism instead of a confession of faith.
First off, the Church "stopped hiding from persecution" because Caesar stopped persecuting.
Jerusalem ceased to be the "headquarters" of the Church within the lifetimes of the Apostles. (They moved first to Antioch, then to Rome.) Jerusalem was largely destroyed after the wars of AD 70 and AD 135. Jewish Christianity largely apostasized into a heresy known as Ebionitism, which rejected the divinity of Christ.
As early as the late 1st C. you have the bishop of Rome, Clement, issuing commands to the church in Corinth. In the late 2nd century, you have Irenaeus of Lyons writing that the sine qua non of orthodoxy is communion with Rome. In the 3rd century, you have Cyprian of Carthage writing about Peter's successor ruling the Church from Rome.
Nothing much "moved" or "changed" when Constantine came around, except that Rome stopped moving Christians into prison cells and the arena.
As far as "pagans entering the Church through water baptism instead of a confession of faith", the Church at Rome always required both of adults. In fact, the "Apostles Creed" is the ancient Roman baptismal creed.
You, with your RCC lens, say the article is “rubbish” and offer, in defense of that opinion, unsupported declaratives about what extra-Biblical reports allegedly say to back up the RCC version of history - which I call rubbish.