i said people are cherrypicking those comments, not necessarily you. He never said batman killing isn't important or an issue.

You are failing to mention that it is Superman's selfless sacrifice that inspired batman to not brand lex and form the justice league. He needed a reason to bring back his moral code.

Alfred literally mentions that these are new rules and batman views everyone including himself as criminals now. There is also a shot of a newspaper during Clark's research that introduces the branding and "killing" as a new phenomenon. The prequel comic confirms that in the 20 years he has changed and didn't kill or wasn't this violent.

Pretty sure we would see it in more of JL in his cut since its 3 hours and he would return back to his old ways. Its why he gives the "men are still good" speech at the end of bvs. He gave a reason for what would push batman to to do this, so he wouldn't do it again.