That is fundamental thing about D&D, pregen characters might have a backstory but never do they force you down a linear progression story path. I and many others have said it before, the overly convoluted nature of the "origin" system has literally hamstrung Larian into 10 times more work than it should be.
The fact all origin characters have a unique totally unlikely "personal" motivation other than "the tadpole did it" is justy bad story telling. A single character (generic_Tav) with a vast network of progression possibilites would be less work and more appealing to players. You create a story in D&D you are not told one.
Then we come to world building. The world is static, unchanging and dull which is simply terrible. In my opinion Larian have designed the game arse about face. First you build a world THEN you write the story. It pretty much writes itself when you have 50 years of D&D lore to work with. They didn't even need to worry about game mechanics as the core ruleset is written in stone.
As an engineer I follow two general rules.
1) If it aint broke dont fix it 2) Make something work, then make it work better.
D&D ruleset and world mechanics aint broke, Larian never even tried to make it work. At he end of the day we all know how the "tadpole" story ends, reject it or accept it.......with all characters. What story lies in the middle is immaterial if the ending is set in stone.
