Also, Jesus prophesied the destruction of the temple in the gospels: "As for these things which you are looking at, the days will come in which there will not be left one stone upon another which will not be torn down," (Luke 21:6, see also Matt. Undoubtedly, if Matthew, Mark, and Luke were written after the destruction of the Temple, they would have included the fulfillment of Christ's prophecy in them.
How strange it would be to leave out something that helps prove Jesus is who he said he was. All the gospels, Acts, and Hebrews at least mention the temple but they do not say anything about its destruction.
Even if it was an argument from silence, that doesn’t mean its wrong.
The Text of the Earliest New Testament Greek Manuscripts.
Understanding Scripture: An Overview of the Bible's Origin, Reliability, and Meaning.
The evidence indicates the Gospels are, indeed, early enough to have been written by eyewitnesses.