God’s final and complete revelation is not thing, but rather a Person, Jesus Christ. He is God’s only Word and God has no other. There is nothing left to be revealed. Jesus is the fullness of God’s revelation because he is God himself.
The Apostles did not receive continuing revelation. They simply taught and recorded that which God had revealed through his Son. Naturally, through time, we receive and attain a better and higher understanding of the revelation of Christ, but it is never a new revelation.
Those who claim to receive continuing revelation must deny that Christ is the fullness of God’s revelation to man. To believe that we need new revelation is to believe that there is something lacking in the revelation of God through Christ. As others have said here, this has nothing to do with God’s active presence in the Church and in the world. We must remember that this is Christ’s Church, guided into all understanding (not new revelation) by the Holy Spirit, so to equate God’s presence in a Church with continuing revelation is a false argument. He is truly present and through his grace we have received the fullness of all revelation (Jesus Christ) which he has entrusted to his Church to preach to the whole world.
This is why no doctrine or dogma of the Church can ever change. It is why we believe today what the Apostles and the early Church Fathers believed 2,000 years ago. It has never changed because Christ can never change.
There are those who receive private revelation but no one in the Church is under any obligation to believe it and no private revelation can change Church doctrine. Simply put, if it conflicts with what the Church holds to be true and what the Church teaches as doctrine then it is a false revelation and the one giving it is a false prophet. This holds with any person, in or out of the Catholic Church. Truth can never conflict with Truth and it is Christ who is the Way the Truth and the Life, not Joseph Smith.