After upgrading to conky-1.19.7-1 I find the display works for a short time and then disappears.
I downgraded to conky-1.19.6-1 and that works fine.
Edit: https://gitlab.archlinux.org/archlinux/packaging/packages/conky/-/issues/2
conky-1.19.7-2 addressed this. It should be in your mirror by now.