Yep, if 0 is working, leave it there for sure. In some cases, even 0 isn't low enough. https://www.damiensymonds.net/desktop-monitor-brightness
Let's leave it at Native for now, I think.
Yes, but not just that! Your photos will look too cold anywhere on the world wide web too. The WWW uses sRGB as its standard, as you well know, and sRGB is a D65 colour space. That's why most labs have sensibly moved to D65 in the last couple of decades.