Pretty much every 'martial artist' is a cultivator.There's also the issue of population vs distance. The villages have a few dozen to maybe a couple hundred. The towns have a few hundred to maybe a thousand. And the cities (which nearly all have cultivators that would slaughter the person) might have a few thousand. The travel time for non-cultivators from city/town/village to city/town/village is anywhere from several weeks to several months to a year. The chances of a non-cultivator actually getting enough kills to activate the tribulation would be infinitesmally small even if they murdered every man, woman, and child they met and would more than likely take decades of dedicated work to reach the number required. Only the insane would do something like that. Especially due to the fact that a mortal has literally 0 chance to survive it.
