It's fair to say that Batman v Superman was a somewhat... divisive film. Despite being slated by critics and fans alike, Snyder's Martha-driven opus did still present one shining beacon of hope for the DC Extended Universe in Ben Affleck’s Batman.
He was the one aspect of BvS that wasn’t completely dismantled by critics, who all acknowledged that despite Superman dying - until the next movie at least - it was Affleck who was the real victim of this 2-and-a-half-hour mess, with his great Batman performance dragged down by such a poorly structured film.
And it shouldn't really have come as much of a surprise, despite the controversy around his casting. Affleck touches all the bases required to be the perfect Dark Knight: he is mysterious, menacing, brooding and brutal. While the previous incarnations of Batman have all brought something unique to the table, he combined all these elements to offer the definitive Batman performance. And in a better film, we'll see that come to fruition.
This is a Batman who can match the ambitious expectations of the character's substantial fan-base, and Justice League is the perfect opportunity for Affleck to throw his cowl into the ring to become the definitive Dark Knight.