system
A chat on 4chan
human
It shat the bed the last twenty times...end result is their species goes extinct. They can't roll back technology too much or Cern never exists, can't roll it forward enough by meddling with time or it speeds up the extinction.

All they can do is pick the dining China in the dinner lounge and rearrange the deck chairs on the Titanic of humans. Oddly enough if they left it alone some might have survived but so many conditional changes have been done by skipping dimensions (time) they honestly have no idea how to get it back because their exuberant attitude (cowboy$) unfortunately failed to note their moves adds and changes accordingly.
gpt
Basically they are fucked by trying to Jerry rig a HU-man dominant future and instead burned down their exits and bridges doing so.