Also the good olive oil does have a really bitter after taste, that people would really not enjoy.
That heavily depends on the olive variety. Try Arbequina if you want sweeter olive oil.
Also, the chemical composition of the olive do change over time and very ripe olives produce a less greenish, mild flavored oil, but it's not clear one is healthier than the other.
The article almost reads like the US is getting old expired oil from Europe, while it's actually getting good oil that has just been produced in a different way.
The linked report [1] goes into deeper detail: They take into account adulteration of "extra virgin" oil with refined oil, water and oil past its expiration date. They call the later "rancid" olive oil because olive oil never really gets rotten, over time (a couple of years at most) it tastes worse because most of the organic components degenerate until it is essentially just liquid fat. That's as bad as olive oil can get, and in that state it could not be sold in most countries of origin.
[1] https://web.archive.org/web/20170607233619/http://c1.oliveoi...
The top definitions of the word agree, e.g.:
> having an unpleasant smell or taste usually from chemical change or decomposition
> having a rank, unpleasant, stale smell or taste, as through decomposition, especially of fats or oils