On some PCs the game is still can be laggy and stuttering.
To reduce some of that you can disable RT in game config file manually.

Here is how:
1. Disable rtx in game and enable dlss.
2. Close the game and open %appdata%\Fatshark\Darktide\user_settings.config using notepad.(C:\Users\*YOUR_USER*\AppData\Roaming\Fatshark\Darktide)
3. Make sure the following settings are set like this:

rt_checkerboard_reflections = false
rt_light_quality = false
rt_mixed_reflections = false
rt_particle_reflections_enabled = false
rt_reflections_enabled = false
rt_shadow_ray_multiplier = 0
rt_transparent_reflections_enabled = false
rtxgi_enabled = false

4. Save changes in config file, restart the game.

This seems to help with the constant FPS stutter during a match.
If the config file keeps resetting above settings, set it to read only after changing the parameters.

source:
https://www.reddit.com/r/DarkTide/comments/z9a2fj/psa_rtx_is_always_on_despite_what_options_you/

also useful video:
https://youtu.be/tJ11KfVsG_c