I am referring to the case where FAANG would make money out of your work in closed sources:"With this FAANG will need to negotiate to use your code in closed sources(...)"

Still I get your point, and they indeed don't need to negotiate to use GPL but, with GPL most of the times the actual developer receives the merit of the work (whatever it means) and more important, the community can use any improvements/features/functionalities that FAANG may develop on top of original work.