Something that worked for me and almost fixed all shuttering/FPS issues:

1. Make sure you VSync is off. In-game, in your video card settings also.
2. Download a tool that allow you to cap FPS on specific application like Radeon Pro or Rivertuner (there's probably other options too). The game runs at 60 FPS, by limiting the FPS to 58 FPS I was able to able tearing/shuttering issues.

Hopefully it will help. Good luck!

Yeah, stuttering is pretty bad for me too, even with vsync off in the area immediately after the first boss I'm getting drops to mid 50s. GPU at 15-35% utilization, none of the CPU cores above 60% or so... If I cap the game to 58, the framerate drops are even lower.

Was encountering that issue as well, partially fixed it by using DXVK + the Dinput FPS fix from PCGW.
It's not 100% perfect but the improvement is substantial, the one downside is you get a short grey screen on level load / respawn.

So, I tried most of the fixes here, some of them improved my issues but didn't fix it.
Uninstalling the game from the SSD and reinstalling it onto my C drive completely fixed the issue. It's the only game on my SSD that seems to have a problem with running off it.
Not sure if it's related, but the second I did that, I could run the game with 0 issues whereas before I was either stuttering to the point of unplayability or straight up unable to leave the tutorial zone due to fps dropping to 1 frame per 10+ seconds.

I've been experimenting again with some other tricks (combo of wrappers settings and various fixes) to get the frame pacing to not be a complete disaster, I've had some limited success, now it's mostly stable most of the time and basically perfect sometimes (Afterburner has a perfectly flat frametime graph besides loads, scrolling feels smoother even when the frametime graph looks like a sawblade), will post again once I'm done doing that with what I've found out.

That's about as good as I can get it
https://youtu.be/nLzzJaPbsdM

Running dgVoodoo + SpecialK
Game needs to be windowed and Vsync disabled
dgVoodoo needs no special config besides bumping the VRAM and removing the logo
SpecialK needs frame limiter to 60 and latent sync on
dgVoodoo alone is better than nothing