There may be something to worry about down the line, but for the record, effective anti-cheats have to be rootkits because ok+ quality cheats generally are. It certainly doesn't take away the possibility of it just loading beforehand in the boot, but it at the very least takes away a good portion of the cheats that bad programmers would make.
When you install anything or use any service there's always going to be that possibility that down the line something you didn't pay attention to is used differently than you intended, but that's the case for every service and every anti-cheat... this one isn't really any different from what we've seen so far.
Also that hugely upvoted post by someone that "works in IT" is mostly complete nonsense. Dude doesn't have a clue. The dude called amd64_sucks is speaking some sense and actually comes from a position of experience in reverse engineering/game hacking/blogging about it.