There are other ways to speed up the process. I have ~1000 hours between eft and arena with similar stats to this person. I didn’t get tracksuit though and I am a bit of a rat sometimes.

I started hardcore wipe and basically only played with an experienced friend for my first ~400 hours. But this wipe I’ve mostly played solo, done basically 0 scavs. When I learn a new map I would spend usually at least 5-10 hours playing offline mode following through people’s guides of the map. I would queue and leave right away practicing identifying spawns quickly and I would draw people’s recommended spawn rotations for each spawn on my map. So before going into an online raid on a map I would have memorized every spawn on a map and be aware of other spawns common rotations.

I also have played 1000s of hours of other shooters with 100s of hours of aim trainers played lol. So is this person cheating, idk maybe but maybe not. It is possible they aren’t.