Bible scholars are leaving Christianity in droves. Why?
I only watched the first two videos (and only half of the second video), but from that I suspect that the main reason they stopped believing was because they had no personal experience of proof.
When I started to get more serious about Christianity, I used to say that I had 99.9% belief in God, but there was always that tiny amount of doubt, that possibility that it was all made up by men. So I used to pray to God that he would increase my faith. Eventually he did that, although not in a way that I had expected! After carrying a heavy load for a long distance I ended up with a back problem that was ongoing for 4 months and not getting any better. Other Chistians laid hands on me and prayed for healing, and I prayed for healing too, but it didn't get any better. Then after 4 months I went to a meeting of an evangelist who had come to my home town (a once in a lifetime event!), and at the end of the meeting he prayed for healing for those that wanted healing from God. I experienced a wonderful tingling feeling enter my head from above and fill down through my torso, that lasted for maybe 10 - 15 seconds and was a very pleasant and enjoyable feeling. After that my back was healed!
The evening before my back was healed, we had a Bible study in my home, and because I had been struggling for months to understand something I asked the pastor who was teaching us, about it, but even he was unable to satisfactorily answer my question. But during the night while I was asleep and having a non-sensical dream, my dream was interupted by three words, then the dream continued. It startled me and I woke up, and I decided that the words (three digits) had to be a page number in my Bible (I only had one Bible at that time!). I went back to sleep, and not having a very good memory it was eventually 4 days later when I remembered while I was at home and had access to my Bible, and when I looked up that page, right at the top of the page was the start of a chapter that was about the subject I had been struggling with - it was an aswer from God! (and also confirmation of Matthew 18:20, "For where two or three are gathered together in my name, there I am in the middle of them").
Those two events, that occured on the same day (Saturday early morning and evening), were enough to raise my faith/belief from 99.9% to 100%. I later realised that that was how God had answered my prayers for increased faith. Once you have had a supernatural experience like that (or even more amazing for some people) it is difficut to loose your faith, because it is a constant reminder of the undeniable reality of our God and Saviour. These scholars, however, I suspect never had a supernatural experience, and spending so much time in research outside the Bible, and especially if they start to believe scientists rather than God's written word, they end up having that tiny doubt of faith growing until they decide the evidence (erroneous or true) inconsistent with God's word is more convincing to them than their initial belief in God's word.
Some though, even after having supernatural proof, still end up not believing - Hebrews 3:7-19 (ESV):
(7) Therefore, as the Holy Spirit says, “Today, if you hear his voice,
(8) do not harden your hearts as in the rebellion, on the day of testing in the wilderness,
(9) where your fathers put me to the test and saw my works for forty years.
(10) Therefore I was provoked with that generation, and said, ‘They always go astray in their heart; they have not known my ways.’
(11) As I swore in my wrath, ‘They shall not enter my rest.’”
(12) Take care, brothers, lest there be in any of you an evil, unbelieving heart, leading you to fall away from the living God.
(13) But exhort one another every day, as long as it is called “today,” that none of you may be hardened by the deceitfulness of sin.
(14) For we have come to share in Christ, if indeed we hold our original confidence firm to the end.
(15) As it is said, “Today, if you hear his voice, do not harden your hearts as in the rebellion.”
(16) For who were those who heard and yet rebelled? Was it not all those who left Egypt led by Moses?
(17) And with whom was he provoked for forty years? Was it not with those who sinned, whose bodies fell in the wilderness?
(18) And to whom did he swear that they would not enter his rest, but to those who were disobedient?
(19) So we see that they were unable to enter because of unbelief.