I've already explained, they didn't make that choice to appeal to the fans, they made that choice because they knew these actors, worked well with them, and knew that they understood the characters and could be trusted to give good, solid performances. Andrea Romano has explained this in many interviews.
So then why not use every movie. Why did they reunite a lot of the old cast for this one and not the others?
Again, Romano has explained this in her interviews. There's more than one person making the decisions here. It's not a monolithic "they," but various tiers of employers and employees with their own views and priorities. The executives in charge of WB Animation want to vary the casts and avoid continuity. Romano likes working with the familiar actors, and she's pushed for them in the past, but has often been overruled. But on occasion, she's been able to convince her employers that the old guard was the best cast for a particular project, and this is one such case. (And this is just my own speculation, but I wonder if maybe the new cast in
Crisis on Two Earths got lukewarm reviews, so they were less willing to gamble with casting the next JL project.)
And really, I don't think they
should use the old cast for every project. A lot of the DC Universe movies have been distinctive enough that they needed a different cast.
The New Frontier benefitted hugely from Kyle Maclachlan as a very Silver-Agey Superman and Jeremy Sisto's really effective Batman (and it was cool to hear Lucy Lawless as Wonder Woman).
Batman: Year One worked well with Bryan Cranston as Gordon and Ben McKenzie as Batman; their voices fit these particular versions of the characters well and helped give the film a distinctive flavor. And of course
Under the Red Hood brought us Bruce Greenwood, who was so good as Batman that he's now playing the role on
Young Justice and is a worthy successor to Conroy.
Conversely, the two
Superman/Batman movies were so ridiculous that I wish they hadn't used the familiar DCAU cast, who deserved better. And there have been disappointments, like James Denton and Christina Hendricks as Superman and Lois in
All-Star Superman.
So yeah, it's a gamble. But it really would not work to use the same cast in every one of these movies, especially the really idiosyncratic ones.
oom and they depicted Jonn Jonzz as a black man (which is a first) and called him John.
