I'm surprised that no one is mentioning the direct effect of petrodollar (or lack thereof).
The gold price drastic increase and USD worst decline is to be be expected, and it's mainly due to the end of petrodollar agreement discussed on HN last year [1]. Somehow the Nasdaq news link is dead now but the Firstpost news is a similar one [2]. The top comment is a golden example of denial (pardon the pun), "This is itself inconsequential" [3]. This can be another Dropbox comment moment of HN. The comment also predicted that "Things will keep running as today probably for the next 20 years", and here we are in just after a year.
The negative effect to USD due to the end of petrodollar is imminent and the writing is on the wall for the gold price to increase sharply when there is no more petrodollar.
[1] U.S.-Saudi petrodollar pact ends after 50 years (325 comments):
https://news.ycombinator.com/item?id=40673567
[2] What was the US-Saudi petrodollar deal that lapsed after 50 years?
https://www.firstpost.com/explainers/what-was-the-us-saudi-p...
[3] U.S.-Saudi petrodollar pact ends after 50 years (top comment):