I have had my own private hack for DayZ since the release (even part of the time it was DayZ Mod). It has a top-down "radar" that I put on my second monitor for better situational awareness in addition to full ESP.
I have spent a lot of time just "watching" people in this game. One thing I've learned - there are some people who are in groups who are really, REALLY fucking good at this game (and I'm also really REALLY bad). Like, Ill just watch from afar and see how people work and they are really good and coordination and execution. Hell, on the few times I try to engage them, even with a complete cheat advantage, I almost always get destroyed.
The number of times I have came across a real cheater I can count on one hand and not within the last say two years. Usually it was a script kiddie would would TP around the map insta killing (it would be great when I would see them show up in my hack first and kill them). Only once did I find another "proper" hacker and he was in reality just using his friends hack. I saw him enter my network bubble (and I his) and he immediately turned to me and started chasing me despite having never seen me. Eventually we got within vocal range and talked a bit about our hacks.
So before you think that people have a lot of cheats, it's probably they just have a group and are really good. But again, I really suck at this game despite being with it from the start and having a full private hack.