I personally believe that THE anti-Christ MUST be a Pope. Who else could it be? A cheesemonger? A cashier at McDonalds? A college professor? C’mon - Jesus was born in a stable. The road to God is paved in irony. Who better than a Pope to be the (ironic) anti-Christ?
He will not know that he is the anti-Christ (and he would be appalled at the suggestion). He will not teach heresy. He will not violate any of the promises that Jesus made to Peter.
But, suppose a Pope were to be very “ecumenical.” Realizing that the Sacrifice of the Mass was an impediment to relations between Catholics and protestants, he could suspend the Sacrifice of the Mass for one year (except, perhaps, during the season of Easter). Catholic parishes were to hold “worship services” similar to protestant services. Such an action is well within the authority of the Roman Pontiff, and cannot be accused of heresy.
And, when ecumenical relationships seem to improve, this “one year” deadline could be extended indefinitely.
Imagine the Catholic Church without the Mass. This is possible, and it would not be heretical. It could be ordered with good intention, but it would destroy the Church. Any Pope could do this. Tomorrow.