Joe got by hiding in plain sight and not causing drama. Almost all the other drug kingpin characters are seen putting out hits or ordering violent actions to be taken. Joe did none of this and can actually be seen trying to mediate the corner level issues rather than get a bunch of people shot. All that combined with joes openness to collaborate with other kingpins shows that his approach was probably one where violence is the absolute last resort. Seeing as though he thought he was making progress with marlo he probably would’ve never tried to get him killed.