I believe EU allows directionally controllable projector headlights (my description, I don't know the official name). These can be brighter because they can be directed away from oncoming traffic. The US, in contrast, is lagging in approving this technology and puts an absolute limit on the brightness.

I'm not surprised there's a disagreement. I'm surprised the disagreement is both sides saying "our way is safer", rather than it being one side saying "this safety benefit isn't worth it" and the other saying "yes it is".

The problem isn't the disagreement in specifications. It's the poor German quality control that doesn't prevent these mistakes from happening. This wasn't a significant problem when the parts were physically different for different markets and the assembly line would ensure the wrong parts weren't present.

> I'm surprised the disagreement is both sides saying "our way is safer"

That's somewhat common for US/EU safety disagreements. Here's the canonical example, from back when the TTIP was still seriously being considered: https://www.forbes.com/sites/nadiaarumugam/2012/10/25/why-am...