Skipping the landline stage means skipping the need to stabilize the situation on the ground, particularly involving crime. There is a lot to be said for the side-effects of landlines, other utilities, a postal service, roads, and so on. Widely exposed public assets need protection, and so they get it, and thus the place is becalmed.
Cell towers are tiny little spots that can be fortified without much concern for the surrounding situation. They don't provide an incentive to care about any troubles in the area.
Do you have a source for that showing causation? Also I don't recall the Amazon area or any of the remote parts of Brazil I've been to having a problem with stability or crime. The crime is in the cities. Where landlines run underground anyway and don't need to be secured.
Cell towers are tiny little spots that can be fortified without much concern for the surrounding situation. They don't provide an incentive to care about any troubles in the area.