it's...not 2025 hardware. it's 2017 (actually 2015) hardware, and Switch 1 games are a known quantity at this point

. It's been 8 years, we know what they look like. Switch 2 upgrades simply up-res the game, increase FPS, maybe add higher-res textures in some cases. But the game logic and the game has to run on Switch 1 to begin with, thus it was designed with that in mind. I'd also point out MP4 has been in development since 2019 and would've only recently been tuned for Switch 2 very, very late in development.
The fact that Metroid Prime 4 is a Switch 1 game and can run at 60 fps with that fidelity actually is impressive, given how weak the tech is. Given the semi open world and whatnot. BotW has an even bigger world and chugs just to barely hit 30 fps most of the time.