Sure. A few hundred years after Christ, they were still considered early church fathers i suppose. Still, it is a later text added, officially, sometime after the rest of it.
Irenaeus affirmed around 120 ad that Revelation was Scripture. He was trained by Polycarp, who was a student of John of Patmos, who wrote it. Polycarp gave Irenaeus his info about the apostles, including what was considered Scripture by the early church. Revelation should be taken seriously as Scripture, though we can debate how exactly to read it.