A claim was made in the OP regarding dating and that essentially all scholars are wrong in dating the Gospels 30-70 years after Jesus' ministry. However, there has been no support or substantial reason given for such an assertion, and as such, it remains baseless opinion.
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You cannot have read the OPs.
The reasons given were
1 It is in the highest degree improbable that men who could write did not or would not have written the events down as and when they happened, because of their importance
2 Luke's prologue shows that other gospels had been written before his. It also supports the idea that he was present when at least some of the events happened
3 Those gospels were most likely to have been Matthew, Mark and John. Mark and John's focus on 'the beginning' is a strong indicator that they were the first ones written
4 There is a considerable amount of internal evidence that shows without doubt that they were written when the events were taking place. Ihaven't posted this evidence, but will do so if requested.
5 The absence of manuscripts that early (AD 33 or thereabouts) is no proof that they did not exist.
6 Jesus must have been doing
something during the 40 days after the resurrection. He was equipping the disciples for the task of preaching - and he knew that the written word was going to be one of the most powerful tools they could have.
He therefore oversaw the writing task, which accounts for their vast literary superiority over any other writings ever produced. It also accounts for why He did no writing of His own.
7 Mark's opening words are: 1 ¶ The beginning of the gospel of Jesus Christ, the Son of God.
This could mean ABOUT Him, or BY Him which would fit very nicely into my theory. It's His work, not somebody else's. But that's a suggestion.
There's some new material there, but you get my drift.