This seems like one of the weirdest games you could remake.
Remakes tend to be prioritized for specific games in a series because that specific game did something that people liked more than for a sequel.
There's only been one Pokemon Snap game. It's not like they know which locations people prefer, or keep making ones that people don't like as much, because they haven't tried any others.
They could throw in some classic locations for nostalgia but I don't see why they'd limit themselves to a remake in this scenario.