Suddenly having funny issues with framerates: Vulkan, Mesa or something else?

Hey friends,

I know that this is a difficult issue to have people try and solve due to how many factors there can be, but this is an odd one for me. To start, here's some info

=== Hardware ===

CPU: 12th Gen Intel(R) Core(TM) i5-12600K
GPU: AMD Radeon RX 6700 XT (navi22, LLVM 16.0.6, DRM 3.52, 6.4.8-gentoo-dist-hardened)
Memory: DDR5 5200
Monitor  Refresh Rate: 165.00 Hz

=== Software ===

Distro: Gentoo
Kernel Version: 6.4.8-gentoo-dist-hardened
Mesa Version: 23.1.5
Vulkan Version: 1.3.250
GCC Version: 13.2.0
xf86-video-amdgpu Version: Up-to-date with the master branch
Display server: X.Org
  xorg-server version: 21.1.8
  xorg-proto version: 2023.2
  
=== Proton Info ===

Have tried GE-Proton versions 7.53 to 8.11

--- Games and their commonly used Steam Launch Options ---

Enderal: Forgotten Stories (Special Edition), Steam App ID 976620
 
PROTON_LOG=1 PROTON_NO_ESYNC=1 DXVK_ASYNC=1 WINE_FULLSCREEN_FSR=1 WINE_FULLSCREEN_FSR_STRENGTH=1 WINEDLLOVERRIDES="xaudio2_7=n,b" PULSE_LATENCY_MSEC=90 =1  LD_PRELOAD="$LD_PRELOAD:/usr/\$LIB/libgamemode.so.0.0.0" gamemoderun %command%

I've also tried without DXVK_ASYNC and adding PROTON_USE_WINED3D=1

Deep Rock Galatic, Steam App ID 548430

No extra launch options. Runs on Linux, but still the weird framerate issues

This issue with low framerates only started happening recently. The earliest I recall seeing these issues was sometime 2 weeks ago. I thought it was something related to the version of GE-Proton I was using. Last time I had a problem was with using the stable version of Mesa but that was several months ago, about 9-10 months.

When I run glxgears I get around 165-170 fps, so I don't think the physical GPU is the issue. Lower-end graphical games run perfectly fine. Nothing else has been running any slower, and I don't think I've made any notable changes to my system that would cause this. Running btop when nothing is running doesn't show any processes that's taking resources it shouldn't. Neither the GPU nor CPU make more noticeable noise or anything, nor does the CPU run hotter when I first got it and started playing games.

Without doing getting really into the weeds, my best guest is something with versions of Mesa or Vulkan. But I wouldn't exactly know. I'm just basing that on the one issue that I had with an older version of Mesa those 9-10 months ago, so I could be completely wrong. I could try with the git versions of each package. I'll see if I can install those and see if anything is better and report back.