I get 30 FPS all the time basically everywhere. Using Vulkan, currently. Cleaned my drivers back to 512.95 (NVidia), and it's running good so far. (Some graphical anomalies are to be expected, just reboot game & it's fixed) Can't get 60 FPS anywhere really outside of smaller maps with Vulkan, but with the custom build and OpenGL I could. Can't stand the hitches, though. That and the worst part of the custom build on OpenGL being performance degradation when facing certain directions after some time. (can spin the camera around when first booting up the game and it'll be capable of 60 FPS in all directions, then after a while, north for example could drop to 30 and lower over time until you restart, Vulkan doesn't have this issue)
This is in good part from my hardware. i5 11600k (4.6 ~ 4.9 GHz), 16GB RAM, GTX 1660 Ti and Windows 11.
The GPU in my case is what is letting down performance on Vulkan from being able to reach 60. From what I've noticed with OpenGL, the graphics look a lot worse even when using the same graphic mods, compared to Vulkan, hence the better / worse performance. It's extremely noticeable, on the title screen especially.