Niners fans absolutely packed SoFi on Sunday, and based on a lot of photos from the game, looked to be more prominent than Rams fans in the building. It is pretty stunning.
There's no way to know the actual split of fans inside the stadium, but 49ers fans clearly showed up in force. This has happened often since the NFL made the puzzling decision to shove two teams in Los Angeles after a 21-year absence from the market.
The Rams certainly have more fans than than the Chargers, but both franchises have dealt with opposing teams taking over their home stadiums.