system
A chat on subreddit /r/wallstreetbets
human
Usa birthrate going down, china has 70 milliom extra men, interest payments on the debt get higher than the deficit which will be around the time the debt has the same value as the market. 
  
 Since fake Americans like paying taxes then dont be surprised when  your 401ks get a wealth tax

gpt
There are currently 7 states that have massive pension problems that taxes on 401ks is on the menu in the next 5 years