The thing about Bay’s Transformers is that he knows how to shoot for scale. Parts of Optimus are allowed to exist offscreen, his size always expressed via high angles/ground-level POVs because our eyes wouldn’t be able to view him so completely.
I don’t think Crosshairs realized how lucky he was that Hound is a big softie because if that was Ironhide, you can bet your ass his head would’ve been blown off without a second thought.