The Dodgers missing out on Soto was a big help to the Giants
The same "trades in the division" problems that the Giants had in pursuing Soto applied to the Dodgers. The Dodgers could use an upgrade in left field and given the depth that LA has in their farm system, they could have put together a really competitive trade package for him.
The Dodgers are always going to be mentioned as a landing spot for any big name and Soto was no exception. LA has a lot of drawing power given how aggressive they are in fielding a contender each year, so taking one less option in Soto off the table for them is a nice ancillary benefit to every team in the NL West including the Giants.
How much this will ultimately matter is an open question. While the Dodgers won't have Soto in 2024, they are still extremely likely to add at least one big name this offseason. They are in a full court press to try and land Shohei Ohtani and are in the running for basically every top free agent starting pitcher on the market. Given that the Giants are competing with LA for all of those guys, it is more likely that how the free agent market shakes out will determine more than the Soto.
That said, the Dodgers looked very vulnerable last year and while they will have Mookie Betts and Freddie Freeman again, there is a realistic possibility that they will miss out on most of the biggest names in free agency. If that happens, they could end up being even worse next year especially since they weren't able to add a bat like Soto's.