Here's why I think so 

1. Robert Pattinson is quite frankly the hottest actor right now, everyone everywhere is admiring his exceptional run of films and his performances. Why wouldn't you want such a big name attached to your franchise? 

2. Can't deny that David and Robert have both embodied possibly the most definitive versions of their characters, or atleast have the best opportunity to do so 

3. The DCU thrives off its tonal differences from project to project, if you see Guy Gardner in Superman, you'd think something like Kyle Chandler's Hal Jordan couldn't exist in the same universe, but it does! And that's the best part about the DCU! The similarities, the parallels and even the differences between Battinson and Corensupes is the exact dynamic you'd want to see in a world's finest film 

4. The Batman is easily the best CBM of this decade thus far, maybe even a top 5 CBM of all time if you ask me, everything about the film and it's spin off the penguin, their success, is not something you want to separate yourself from, rather attaching the DCU to it will be an exponential boost, bringing in characters like Blue Beetle from the DCEU isn't even a fraction of what the merger with Battinson could do for the DCU and everyone knows that 

5. Matt Reeves has a vision for the batman, and it must be respected, no doubt about it, he should and will complete his trilogy the way he wants, afterwards for other projects, Sam Raimi or James Mangold can take over the helm for Batman in the DCU, if Matt wishes not to continue. 

6. It can fit in perfectly, get this- Superman is set in 2025 and it states that Superman started out 3 years ago in 2022, that's the same year The Batman is set in. Many sources indicate that The Batman Part 2 will pick up right where Penguin ended, if Matt wishes, he could conclude his plans for a trilogy will before 2025 in the DCU timeline, no conflicts with Superman's timeline and setting, and by the time 2026 rolls around for Battinson, he'd be much more experienced and "DCU ready" than what we saw of him in The Batman 2022

What is the hate surrounding the merger? It seems to be the best choice easily