Eh...Batman Begins was apparently tracking relatively low according to a few articles I've read, although coming off a franchise killing disaster with an almost universally popular character is different to coming off a franchise almost-killing disaster with less popular character.
The opposite. It was tracking high and expected to pull in around $100M for its opening weekend. It did $75M. Then came the freak-outs of it all being over before it started. Until WOM kicked in and it held like glue for the rest of that summer. Batman Begins pulling in $205M off that opening was great.
Regarding Pine, the person in the video to suggest its over if Wonder Woman under-performs is kind of an idiot. He's the supporting character. If this flat-lines (and I do tend to think it will pay for Batman vs Superman and Suicide Squad burning audiences), that will be on DC itself and Gadot.