1. Geoff threw out the entire planned storyline when Trump got elected and everyone in the comic industry went batshit crazy calling anyone they didn't like Nazis. So he rewrote the story to make it a commentary on such fear/hatemongering with a much stronger denouncement of Adrian Veidt AND Dr Manhattan for being horrible evil people who were the real villains of Watchmen
I'm going to need some more elaboration on this as I'm curious as to if this effected certain plot elements like the Superman Theory, which asked the intriguing question of why most of the world's metahumans were from the United States,
2. As part of this, he also fucked up by declaring "NO FUCKING CROSSOVERS"; which bit him in the ass and then some, as Dan DiDio got pissy that he was going to miss out on a big sales boost for the DC line. So he purposely let Tom King kill off/make into a murderer Wally West (fucking up any chance of a Wally/Doctor Manhattan showdown) and gave Supeman AND the Legion to Bendis, who fucked over Geoff's plan for Jor-El to be a patsy/slave of Dr Manhattan and the subplot from Rebirth where Saturn Girl was going to try and fix Manhattan's fucking with the timeline, as Bendis decided to create his own new Legion; forcing that plot thread to be aborted and a last minute insertion of the Bendis Legion in the final battle. And for added insult to injury, Scott Snyder was given TWO major minis to be the "official fix/finale for Rebirth" after Snyder agreed to do a story with a TON of tie-ins.
On one hand I can see this as a fuck up because of the lost potential revenue of tie-ins, but I look at it as Johns trying to protect the integrity of his story as
Doomsday Clock was more "literary" than his other works. It was clear that he was trying to emulate Moore's style on
Watchmen. I fucking LOATHE DiDio for how he attempted to derail the story, but I think part of why he killed/derailed Wally was because of his hatred of the original sidekick characters. I present what happened to Dick Grayson and Roy Harper during that time as evidence. The handling of the Legion was what really sent me over the edge because I was eagerly anticipating their return when I saw Saturn Girl in Rebirth, and Bendis' Legion was incredibly godawful. Don't get me started on the Death Metal tie-ins. Some of them were okay (hell, Mark Waid's contribution was readable) but the majority of them were dogs hit.
Tying into Bob Chipman, I think many who worked at DC at the time (DiDio, included) had the same attitude towards the fans--notably how they believe that we don't know what we want and we should accept what they give us out of gratitude.
Rebirth was effectively an apology for how the company handled
The New 52 and the failed
DC You initiatives. Geoff Johns was the front man and fans as a whole loved it, but I could imagine that DiDio and many creators were seething. However, Geoff was getting more involved with the film side of the company and I suspect that his influence began to diminish. Johns soon quit as CCO and DiDio saw an opportunity to force his vision on the DCU, fans be damned, and thus we have the clusterfuck we have now.
3. Geoff refusing to remove Gary "slow as fuck" Frank from the book, resulting in the delays.
I suspect Geoff's "moonlighting" as a producer interfered as well as he was developing
Stargirl and writing scripts for
Titans and I believe
Doom Patrol as well, but don't quote me on the former.
Removing Frank would have been problematic. Yes, it would have prevented delays, but at the cost of artistic consistency. Look at
Infinite Crisis as an example. Phil Jimenez, another slow artist whose quality turns to shit if you rush him, was the original artist assigned to it, but he couldn't keep up with the deadlines so they brought in other artists to pinch hit for him. How many artists? We had George Perez, Jerry Ordway, and Ivan Reis brought on and the series reads rather haphazardly because of it. As slow as Gary Frank is, I would have rather seen him to it to the end rather than bring on other artists with different styles to muddy the series. If DC wanted a faster, more reliable artist, they should have brought on one of their workhorses like Ivan Reis though I don't know if he would be able to emulate the
Watchmen style. Maybe they should've brought in Jason Fabok instead, but I don't know how fast he works.