I don't give much weight to the church of 381 A.D. The church had gradually drifted away from early Christian teaching, and by 381 A.D. their teachings and practices were far removed, and no longer apostolic. I'd go with the teachings of Irenæus any time before I would accede to those who wrote in 381 A.D.It seems to me that putting any weight on Irenaeus' writings is a problem. To start with he was an outspoken chiliast, which was condemned by the church as heresey in 381AD. Second he was known for whacky errors such as claiming that Christ was in his 50's when crucified. Finally, and most importantly in this context the passage you just quoted describes his fundamentally erroneous eschatology in which the world would only go 6000 years before the millennium. This obviously didn't happen so why, exactly, should we consider him an authoritative voice on eschatology.
I gave Irenæus as an example. The second century church in general were "chiliasts". Why? Because the author of Revelation was a "chiliast", and contrary to the opinion of preterists, and Revelation was written after 70 A.D. Oh, I know preterists must deny this or their whole system crumbles. But both internal and external evidence seems to show that it was written considerably later:
https://www.christiancourier.com/articl ... on-written