Hi Brice,

>But like you noted it would 
> be specific
> to loadable modules and not built-in ones since `kernel-arguments` is 
> just an OS
> field, which AFAIK can't be influenced by a service.

There's no one stopping us from extending operating-system-kernel-arguments,
which already exists as a helper procedure, to also call
operating-system-services and check those for the command line arguments
to add (see gnu/system.scm).