Two things would have to happen for the kidnapping to end, without a functioning government/police force: (1) the people in the gang controlled areas would have to stop collaborating with the gangs and stand up to them… which would get many of them killed, so that won’t happen - no matter how miserable people’s lives are, they still want to live; and (2) people would have to be willing to allow their kidnapped loved ones to die… which not only won’t happen, but would lead to entire families of the original victims also being kidnapped and killed.
Maybe 10, 15 years ago, it could have been stopped by people working together to stand against it, but at this point, any knucklehead with a gun can become a kidnapper. Some people with weapons have tried to fight back, but they are often outnumbered and killed anyway, since the kidnappers work in teams, and have much better guns.
Just as an aside though… “extortion taxes” aren’t unusual in the U.S. either. A relative who always had a couple of small businesses in Haiti immigrated to NYC, and set up a similar small business in the Bronx in the late 1960s. He lasted about 2 years before giving up, since he would not pay the local police for protection; he was shocked that this kind of thing happened here. During the crack epidemic, in my neighborhood it was easy to tell which businesses were “being protected” by the drug dealers - the other businesses would close down within less than 6 months.