It is defended regularly by Early church fathers such as:
Ignatius to the Trallians (c. AD 70-115)
“For Says the Scripture, ‘May bodies of the saints that slept arose,’ their graves being opened. He descended, indeed, into Hades alone, but He arose accompanied by a multitude” (chap. Ix, The Ante-Nicene Fathers, vol. I, p. 70).
Ignatius to the Magnesians (c. AD 70-115)
“…[T]herefore endure, that we may be found the disciples of Jesus Christ, our only Master—how shall we be able to live apart from Him, whose disciples the prophets themselves in the Spirit did wait for Him as their Teacher? And therefore He who they rightly waited for, being come, raised them from the dead” [Chap. IX] (Alexander Roberts and James Donaldson, eds. The Ante-Nicene Fathers, vol. I (1885). Reprinted by Grand Rapids, MI: Eerdmans, p. 62. Emphasis added in all these citations).
Irenaeus (c. AD 120-200)
“…He [Christ] suffered who can lead those souls aloft that followed His ascension. This event was also an indication of the fact that when the holy hour of Christ descended [to Hades], many souls ascended and were seen in their bodies” (Fragments from the Lost Writings of Irenaeus XXVIII, Ante-Nicene Fathers, vol. I, Alexander Roberts, ibid., 572-573).
Clement of Alexandria (c. AD 155-200)
“‘But those who had fallen asleep descended dead, but ascended alive.’ Further, the Gospel says, ‘that many bodies of those that slept arose,’—plainly as having been translated to a better state” (Alexander Roberts, ed. Stromata, Ante-Nicene Fathers, vol. II, chap. VI, 491).
This does not include the multiple times the phrase was quoted by later church Fathers (Tertullian, Hippolytus, Origen, Cyril, etc). If one suggests that it was added to the text, they must first grapple with its extended use in these and other very early documents and decide how an error was placed within the text so early in transmission.