Listening to them, it's pretty clear the extradition bill and the erosion of their human rights is a driving force.
If you want to talk about human rights, please read through the first instance of re-interpretation by China of Basic law of Hong Kong, when Hong Kong people requested China to re-interpret the basic law against basic Human Rights not to allow mainland spouses to enter Hong Kong. So Hong Kong is still denying the most basic human right of a family, but at that time it was in the interest of Hong Kong people and bad for Chinese spouses, so no protest against it neither any backlash. Indeed overall society was very happy at the cost of infringing human rights. You do something wrong once and open the doors, it will come to bite later. If at that time Hong Kong people would not have involved China for re-interpretation, it would have brought 150,000 people from across the border, along with it some more hardships, but would not have eroded the freedom. Hong Kong people chose prosperity over freedom and now will pay for it.
So fighting for human rights now is just a farce, main reason is, get rich quick does not work, majority live in prison cell size apartment(again by choice) and have no way to change it.
https://www.nytimes.com/interactive/2019/07/22/world/asia/ho...
It will give you true picture of how Hong Kong lost to mainland cities in terms of quality of life and innovation. So economy is the main root of all this frustration and protest. Extradition bill is just the spark.