Crucially you cannot stop the cart you're on, it trudges forward at a mostly static pace through the level. This means you have to run through zones a couple times to learn the timings for certain pokemon to appear. At some point you unlock apples (lures) and rocks (activators) which you can use to influence the movements that pokemon make through those zones.
It culminates in things like seeing a Magikarp early on in a river rapids level, lining up your shot perfectly to hit it with a stone so it flies into a waterfall, that allows it to evolve and you'll want to get your camera pointed up for the dramatic moment it bursts back out through the waterfall. You get extra points for things like the pokemon being centered in the shot, them facing the camera, making specific movements, rare happenings (like evolutions, or using moves), etc.
So I'd say so, yeah. It lacks the grandiose appeal that Mario 64 had at the time but I'd say it beats out Tetris no matter what way you look at it.
Back in the day you could take your cartridge to a blockbuster and print out your in game photos too (or something like that). That was the coolest thing in existence.
The new one looks like a pretty faithful sequel, even, pointlessly, drawing on some of the canon from the first game. I think it will great.
Never played Pokémon Snap, but if the gameplay resembles even a little the photography side-game of Beyond Good and Evil, or Subnautica, I'd probably find it fun to an extent. And beating Tetris gameplay, for me, is a pretty low bar. About the only thing I liked about it was the memorable music - as a kid, I never had patience to become good at it. The racing game on the same "100-in-1" handheld, now, that was another thing :).