Good reads and low writes are a symptom of a misaligned partition. You've posted info from Linux and Windows; while transitioning between the different flavors of operating systems the drive could've been improperly or never cleaned by the partition managers in use. You keep trying to shift the blame on WD or AsRock, you even provided firmware files and hundreds of lines of mostly irrelevant Linux commands dumps. And when you're asked about relevant settings you answer with dismissive one-liners.
As for the "intentional" part, it is widely known that in case of RMA, there is a very small chance WD will replace the "defective" drive with a refurbished one, a small chance WD will replace the defective drive with the same model and a very high chance WD will replace the drive with an upgraded one. It's a bit of a crapshoot, but, hey, you just got a 2TB drive for the cost of a 1TB, which keeps on skewing the probability in a certain direction. I don't like to believe this is what happened, I don't want to believe that this is what happened, but it wouldn't be the first time something like this happened.
There is a very small chance AsRock has a bug in their firmware, but it's really small, since the AGESA code comes from AMD and, apart from hiding or exposing certain settings and reskinning, it's mostly left untouched by the motherboard manufacturers. As for a bug in the hardware design, sure, this can also happen, but, again unlikely, since there's a lot of copy/paste here as well.
So, it's either a widespread problem with the AMD firmware/chipsets or a case of PEBCAK.