It's easy for a 'scooper' to come up with LOGICAL plans based on what the fans would want. It's much harder for them to predict the out-of-left-field crap the ignoramuses at WB will actually come up with, like a Wonder Twins movie.
I definitely do not believe that WB has a 4-year plan in place, nor that it would make as much logical sense as that.
We've seen how hard it is to adapt superheroes to the screen accurately. Feige and Snyder are basically the only ones who've been able to do a consistently good job of it this century, with great casting, good-looking costumes and reasonably faithful plots. Raimi also did fine with the Spider-Man movies, except when he tried to move out of 1960s Spider-Man, the only material he read growing up, and into the Venom story line.
DC immediately went off the rails as soon as Snyder left, with almost every new character cast extremely poorly. They appear to have only one consistent plan for DC, and that is to race-swap as many white characters as possible. They have a politically correct corporate edict based on a social agenda, not an agenda based on a love for the comic books and a desire to give the fans what they want. Some other directors can make good movies like the Nolan trilogy and Joker, but they're not comic-book accurate. X-Men was sometimes good, but rarely very accurate. Deadpool was their most accurate movie, and naturally was their most successful.
Bottom line, I don't think there's anyone else out there in Hollywood who will be able to adapt DC comics into movies well and accurately besides Snyder. There's nothing to look forward to unless he's running their universe.
It's also simply not true that he didn't have plans to run a complete DCEU shared universe. That sounds like a grifter, I mean a 'scooper,' trying to falsely represent reality in order to make his 'scoop' sound more plausible. He had many plans to produce films beyond just his 5 films, such as Affleck's Batman movie, a Batman & Robin TV series, introduction of Carrie Kelley, another Superman movie, a Ryan Choi Atom movie, likely something with John Stewart and the Green Lanterns. And he would have been able to fit in these other ideas that came up like the Amazons movie. The Snyders were producing all the spinoffs while they were there, Suicide Squad, Wonder Woman, Aquaman. That would have continued. It doesn't rule out that Affleck's Batman might have been 'retired,' but that's no different than MCU retiring Iron Man, Widow or Cap. Flashback movies could still be done, and a new generation could step in to fill those characters' shoes. Bruce Wayne is the least relatable aspect of Batman, so having someone else inherit the mantle could be quite marketable.
I couldn't disagree with you more strongly and wholeheartedly. Superman's goal is to save lives, and the way you save lives sometimes is by killing murderers. Superman killed General Zod in Superman II. He killed him in John Byrne's 1980s comics. Snyder's portrayal of Superman killing Zod was 100% accurate, traditional and faithful to the character. And, in fact, much softer than those past two examples, because it was purely defensive. These two examples are pre-meditated executions of a Zod who has already had his powers taken away. But if the scene is brightly lit and there's joyful music playing, then I guess the killing is okay?