Did you noticed that even with enabled ray tracing theres still ssr rendering?
It maybe increases performance a bit, but makes reflections cheaper and Im here to tell you how to turn SSR off without affecting RT.

Straight to the point, simply just type this command in console

If you also want to increase rt quality type this:

Perhaps you'll face to the problem it's just don't work, then do this:
1) Download Cheat Engine https://www.cheatengine.org/
2) Download the latest version of DOOMEternalx64vk.CT from here https://fearlessrevolution.com/viewtopic.php?t=11889
3) Launch the Cheat Engine and your game
4) In Cheat Engine click glowing button with monitor icon
5) Then select DOOM Eternal from list
6) Then click to folder button right next to monitor button
7) Select DOOMEternalx64vk.CT you downloaded previously
8) In below tab click the highest checkbox
9) Check the "Unrestrict Console Commands/CVars & Bind"
10) In game try to type commands again, this time it should work