Thank you very much for your test of the NH-U12S. Unfortunately, things are not as simple with the AMD mounting as you seem to think… The reason why we had to go from our standard 83mm hole spacing to 78mm hole spacing for the U14S, U12S and U9S is that in standard orientation (parallel to the RAM slots), only the 78mm allows the brackets to clear the RAM slots. As your own photo nicely shows, a bar with wider hole spacing would block the RAM: https://smallformfactor.net/wp-content/uploads/DSCN0560.jpg
This is also why we can not offer 90° brackets for all the coolers using the normal 83mm brackets. So in short, using the same brackets for all coolers isn’t possible and offering the option to turn the coolers by 90° would only be technically possible for the U14S/U12S/U9S. Now the problem is that only a small portion of our customers use AMD and out of these, around 95% use the cooler in standard orientation (parallel to the RAM in the case of tower coolers). So it wouldn’t really make sense to increase the price of the coolers in order to include a second set of AMD brackets. With that being said, things look a bit different on the upcoming AM4 platform, so we aim to offer the option to install all coolers in both orientations on this platform.