Comment by dralley

You can get the gist by reading through this thread

https://www.reddit.com/r/hardware/comments/dzdacg/userbenchm...

It wasn't one event, more like the ratings for CPUs just became laughably, transparently, utterly worthless, to the point where Intel i3 laptop CPUs were scoring higher than top-end AMD Threadripper CPUs. And they refused to acknowledge any issues.

Within a month or two after AMD started shipping CPUs with more than 8 cores, they tweaked the algorithm to ignore >8 cores. And various other ridiculous changes that hurt AMD's rankings.