Alot of known decent oils do test poorly in terms of additive content... this is true, many oils folks swear by appear to be very additive-depleted compared to others. If they work, it's hard to debate. Oil is like religion.

GT-1 from "back in the day" actually contained a small amount of copper as an additive, according to recent tests of NOS oil. I've got two cases of green gt-1 left... ..certain types of Pennzoil also had some copper deliberately in it as the test below shows. I don't think anyone does that anymore...but these tests of older oil show, most of them were not really all that.

https://www.blackstone-labs.com/Newsletters/Gas-Diesel/October-1-2012.php