The other reason I doubt this is likely is because when AT&T pulled that power move on WB, HBO Max was just launching (badly) and they were desperate for something to get it some buzz and build a base. Especially with all their delayed launch stuff like the Friends reunion. Like, WB had nearly a whole damn movie already made and sitting on a shelf featuring major actors as huge name brand characters with an online fanbase crying for it, so of course they pulled rank to make them get it out there and help sell their struggling service. But that was before they got WB's whole 2021 slate of A-list movies to build buzz and a subscriber base, and by the time a JL sequel would happen, they'll have whole slate worth of original content regularly flowing in, including DC content, so the JL sequel won't look like nearly as big a "get" as the Snyder Cut did to them in May 2020. It would cost them way more, and they'll need it way less.