I don't hate Ben Affleck, but with the huge success of The Batman there is no reason to bring him back.
Unless you want to do a live action version of The Dark Knight Returns, he'd be kinda great for that in maybe 10 years.
This is actually part of the mess the former management left for the new one to sort out.
"Joker" and "The Batman" exist in their own "pocket universes". If the outline of the Joker we saw at the end of "The Batman" is the real thing (the character was not named) then they do not even exist in the same "pocket universe", not to mention that "Joker" was set in the early '80s. Anyway, a sequel to "The Batman" is now in doubt, as DC wasn't happy with the box office (IMHO this is unfair as that production was ravaged by COVID and the big set pieces suffered from it). "Joker" already has a sequel.
Viewers actually like Ben Affleck as Bruce Wayne. His Batman is on the average but many think that Affleck nailed BW in a way no one did before (I agree). The single biggest problem the DCEU caused to itself was that we never had a Batman movie. He was always a co-host with someone else, while even Aquaman, The Flash, Shazam, Batgirl, Supergirl and Wonder Woman got their movies. Even worse, Affleck's Batman
had to be phased out, full stop. This is why they called Michael Keaton to portray an older Batman who barely appeared in "Batgirl", "Aquaman 2" and "The Flash".
When "Zack Snyder's Justice League" almost crashed HBO Max due to the number of people that connected at the same time (beside almost crashing the various streaming services around the world who had the rights),
the very first thing the management said was "We will not go forward with the Snyderverse". They looked at the Snyder's Cut only as a "what if" that was good to pimp up their streaming service, nothing else. When the new management took over, two of these bozos were sent away and the third (Walter Hamada) will be next. Now they are trying to solve the mess and restore a DCEU with characters the fans actually want.
[BTW, when "Suicide Squad" came out, there was a furry of leaks about how the final cut was far different from the original one by David Ayers. While there is always the stupid who babbles away something, these rumors are never taken seriously. Those who work on a movie are actually very protective of it, at every level. A flurry of leaks is almost always caused by disgruntled crews - from the Director to the catering - who feel the need to warn the public that it is about to be conned; this is why it is usually believable. The same reason explains, for example, why we had all those leaks from the "Batgirl" screenings, as the public does the same.]
Next problem for David Zaslav: "The Flash". Not only we have Ezra Miller on the run but the plot was built specifically to pave the way for the new, safe and diverse Holy Trinity of Batgirl, (a latino) Supergirl and Wonder Woman. "Batgirl" was thankfully nuked, "Supergirl" is in pre-production but she is first introduced in "The Flash". If Zaslav decides to nuke "Supergirl" with minimal loss then her subplot in "The Flash" will make little sense. This can be fixed with reshoots and word from the test screenings is that the movie itself is good. All of this still won't solve the biggest problem, which is Ezra Miller. What to do?
Reshooting the movie with another actor will cost, reportedly, $100 millions. This on top of the $300 millions already spent on production and pre-marketing. Even if you find another good actor on the spot, we would still talk about a movie recreated from the ground up. Are the other actors available? When? Should we just replace the Flash digitally in already existing scenes? Is the rewritten script as good as the original one? DC would, basically, throw $400 millions on a gamble.
The other solution is to sink "The Flash", to sink "Supergirl", call back Affleck (who already said yes) and Cavill (he is "interested"), keep Gal Gadot (as even I would ask for a female presence in the team) and move on from there with a new slate of movies. "Aquaman 2" is fine, "Shazam 2" is, reportedly, good and it is isolated from the main storyline anyway. The same can be said for "Blue Beetle" and "Black Canary" - with only their quality affecting their going forward or cancellation.
tl;dr: At the end, the DCEU ignored the enthusiastic reception of Zack Snyder's Justice League, and betted the bank on HBO Max, "Birds of Prey", "Wonder Woman '84", "Batgirl", "Supergirl" and the they/them Ezra Miller - leaving then the consequences to someone else. Zaslav inherited both the mess of the past and the mess of the future - messes that were dictated by wokeness and wokeness alone. Zaslav right now is desperate to cut costs and he is lucky that he can compensate some sinkings with tax write downs (allowed by the fact that there was a merger). It is my understanding that this window will close this August so he needs to decide quickly.
It is true that shake ups at HBO Max are in the air, as the collapse of Netflix is scaring every streaming service out there (the first earnings report for the new merger could be already out today, along with the future roadmap). I agree that the movies in general are in need of a new distribution model, I don't agree that they should act like if the pandemic is in the rearview and that we are ready to return to "theatrical only" - but this is not my call to make.