Except Binge On doesn't work with YouTube and (unfortunately) my daughter spends way too much time there.
You actually still get a benefit on Youtube. Even if the usage on youtube isn't zero-rated, it's still down throttled, so the amount of usage is limited. T-Mobile's quoting a 3 to 1 savings in usage, apparently.
So at the end of the day, all of her hanging out on YouTube will have less of an impact on your usage than without BingeOn enabled.