Enable volume management in Thunar on a Guix System

On my system I have installed both thunar and thunar-volman:

$ guix package --list-installed | grep thunar
thunar-volman	0.9.5	out	/gnu/store/yp5xyyvvc59ivghszgyfwy3izd8jvqz0-thunar-volman-0.9.5
thunar	1.8.16	out	/gnu/store/4hy62y05g34hwrhlyk8vjhka47d5bmhq-thunar-1.8.16

But when volume management is disabled the advanced settings looks like follows: But gvfs is installed, at least according to the package manager.

$ guix package --list-installed | grep gvfs
gvfs	1.40.1	out	/gnu/store/qg1827ai9j5raypmdajw3k7cibsqdykz-gvfs-1.40.1

Is this a packaging issue or, as I think I've read before, is it that Guix hasn't solved how to deal with dynamic dependencies?