I'm all for banning it. But let's take an honest look at the election predictions and notice PA will almost certainly be the deciding state in November. Eastern PA is solid blue, so the election effectively comes down to Western PA, where fracking is a single issue vote.
Perfection is the enemy of progress. We have a two party system and that's not going away in 2 months. She can say she'll ban it and Trump wins PA, or she can reverse course, opt for greater regulation, and have a chance to be the most climate forward president in US history.