The Greek term for antichrist has a twofold meaning. It refers to that which is anti, or opposed to, Christ. It may also refer to a
false Christ, one in the place of Christ. All people, organizations, or groups that falsely claim to represent Christ or claim to be the
Messiah or that oppose Christ and his disciples can properly be called antichrists.—1Jo 2:22.
Christendom is antichrist because it falsely claims to represent Christ (and his teachings) while they teach doctrines of men (often of Pagan origin,
often tracing all the way back to Babylon, making it also part of Babylon the Great). It also opposes Christ and his disciples.
George Soros is not the antichrist (as in applied to a singular person) in the sense that he would be "a false Christ, one in the place
of Christ" (like all popes claiming to be the vicar of Christ), nor does he "falsely claim to represent Christ or claim to be the Messiah".
He can possibly be described as "antichrist" (as an adjective) in the sense that he opposes Christ and his disciples but that counts for many
people.