Been thinking and the theatrical cut of JL, Synder was at a lose lose, if it did well then WB would've chalked it up to all the additional reshoot material and would probably have that be the blue print going forward thus ending the Snyder-verse, or if it did poorly (like it did) ending the Snyder-verse anyway.
Especially since the marketing leaned so much on the BvS aspect, the main fight didn't happen well into the UE. I would say $800m for BvS is actually a pretty good number now it is all said and done.