Sonic Frontiers: Poor performance with mods on Linux (CachyOS)

[resbit-aidan]

What the title says. Without mods the game seems to run perfectly fine but with mods enabled the game has very inconsistent frame pacing and can't go beyond the 32-38 FPS range, despite only using about 40% of my GPU. This happens on both X11 and Wayland and regardless of what Proton version I use. I have a dual-boot Windows/Linux setup and on Windows the game runs at a smooth 60 FPS with or without mods, so it's a Linux-only issue for me.

Specs:
OS: CachyOS
Kernel: Linux 7.0.11-1-cachyos
DE: KDE Plasma 6.6.5
CPU: Intel Core i7-14700F (28) @ 5.40 GHz
GPU: NVIDIA GeForce RTX 4060 Ti (8 GB)

[PoloAP2000]

I can attest to a part of the issue here.
I'm playing on Windows and.....
When I use mods which are a wide variety, the game for some reason seems to be stuck at 40 FPS minimum.
Meanwhile, when I turn off mods, it goes back to playing entirely fine at a smooth 60.
Heck, even the overhaul mod Frontiers Revisited with its current demo version, plays at 60 just fine.
Something doesn't feel right about this.

Specs:
OS: Windows 11 Pro
RAM: 32 GBs
CPU: Intel Core i7-4790K @ 4.00 GHz
GPU: NVIDIA Geforce RTX 5060