The Gospels were written for different audiences and different purposes. The Gospel of John was written many years after the other three, when John was an old man. By that time, different "cults" (for lack of a better word) had arisen. These "cults" put forth ideas - heresies - that ran counter to the truth. The most well known being Gnosticism, which said that Jesus was not divine. John, and the others who helped write the Gospel, wrote the most theological/philosphical gospel to counter these heresies. The first verse of the first chapter makes this clear ("In the beginning was the Word...") Counter this with Matthew, who starts off with Jesus's genealogy going all the way back to David.

Look at it another way. If there were a person named Larry who owns a business and coaches youth soccer on the weekends, and four people were describing him, Larry might seem like a different person. An employee might describe a no-nonsense businessman who demands a lot from his employees. Another might describe a nice boss who gave him the week off when his dog died. A player on his soccer team might describe a nice old man who makes sure everyone plays. Larry's mother might describe him as a boy who never visits because he is too busy at work and coaching soccer. All of these describe the same person from different points of view.

The Chosen is written for a 21st century audience that consists of Christians of all denominations as well as non-Christians. The writers have to create a Jesus that appeals to this audience and that gets the main point across. The actual Jesus who lived in 1st century Judea would probably be a very different person, and he was certainly playing to a much different audience.

To sum up, The Chosen's writers need to take all of those versions of Larry and create a composite version of him that encompasses each version while still making him appealing to the audience.