You can add the capabilities manually if you copy the binary out of the store.
sudo setcap 'CAP_SYS_RESOURCE=+ep' ./whatever/filepath
Capabilities will be integrated into guix later:
https://lists.gnu.org/archive/html/guix-patches/2023-02/msg00700.html

But even then, the package doesn't work with PulseAudio due to incorrect ladspa plugin name.
The attached files contain the fix I use.

Because you use pipewire, it's possible NoiseTorch will work without my patch. I think it's still required.
But noise-supression-for-voice also easily supports pipewire without NoiseTorch, so you can just use that.