I'm okay with freeze breath. But I will concede that of all Superman's powers, for reasons that I can't quite put my finger on, it has the potential to be the most immersion-breaking power for this 'realism based' Superman. I'm not sure why anti-gravity flight, super-strength, super-speed, X-ray vision, and heat vision all seem to work. I dunno, anyway, I'm okay with freeze breath for this Superman but (even if not entirely logical) somehow I find myself acknowledging the concerns that some have that it will weigh too much toward feeling unrealistic.
I do trust Snyder's judgment about it. If we don't see freeze breath used, it will probably be because Snyder and the producers didn't feel it worked for whatever reasons. If we do see it, it means they were satisfied that it works great. And it probably will for us to.