Some of those stories don’t make much sense to be developed that way. For example, the Gospels go to great lengths to attach Jesus to King David, and part of that is a conveluted census story to get him to be born in Bethlehem. If you want your Messiah to be from Bethlehem, then why not just make him be from Bethlehem?
Conversely, if he was a real person from the poduck village known as Nazareth, then it makes more sense. They still want to make the King David connection, so they invent this census story so he can be born in the “right” place.
Then there’s the problem that he died in a manner reserved for the dregs of society. What kind of god does that? This is a really big deal to people of the time. They care a lot about having a decent burial, and crucifixion victims are left to have their bodies picked at by carrion animals and then tossed into a mass pit grave. No one at the time would have come up with this fate for their revered figure.
So again, they’re dealing with a real person with widely known facts about his life, and it’s really inconvenient for spreading their message. So they cram this Nicodemus guy in the story as a rich benifactor. He has some political pull to take Jesus body down and put it in a brand new fancy tomb. He has little else to do in the story, and isn’t mentioned in Acts or by Paul or anywhere else. He only gets mentioned by John, which is the latest gospel.
So likely Nicodemus gets inserted in there to deal with the manner that Jesus died, but the story of his death wouldn’t have been a method they’d make up in the first place.