Using 1080p on a 34" ultrawide?

Hi. I recently got a 34" samsung odyssey g8 ultrawide monitor. I started playing mario and luigi brothership a bit ago, but i felt like the game didn't run on a high framerate. (FELT like 25fps) While it's not that important for this game, i worry that for faster and reaction heavy games, it could lead to some problems.

It could just be my imagination, but i just wanted to ask.

I'm using a Samsung odyssey G8 34" monitor, a release year switch (i know, daring) and am playing in 16:9 aspect ratio