Cli smb browsing (avahi/wsdd) not working at all

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1

I was seeking to get autofs-like behaviour for smb-based servers/shares by leveraging gio list smb:// and gio mount ....

My starting point is nemo working with Network browsing.
I can also use e.g. gio mount smb://192.168.1.81/scan/ to do a mount like in nemo, which results in

$ ls -1 /run/user/1000/gvfs/
'smb-share:server=192.168.1.81,share=scan'

BUT:

  1. I get
    $ gio list smb://
gio: smb:///: The specified location is not mounted
  2. nemo does not show NixOS smb servers, only NAS and VMs. It appears to be the same list I get as with avahi-browse -rt -a | grep smb. I understand this to be related to (not having) wsdd, but simply enabling the samba-wsdd service on some of the NixOS servers doesn’t make a difference in nemo, and no matter what I do, I keep getting the result under (1)
  3. I’ve tried manually running wsdd -D on a client, and then /nix/store/7z2zldyzgy7973nr9ipk7ksv85savqh5-gvfs-1.56.1/libexec/gvfsd-network, which gives me Couldn't create directory monitor on wsdd:///. Error: Automount failed: Failed to spawn the underlying wsdd daemon. (The gvfs store path was taken from $GIO_EXTRA_MODULES)
  4. I tried enabling avahi on on server, but I get a warning that something else is running on 5353, and the server still doesn’t show up on a client with avahi-browse or nemo
  5. On server and client I now have:
     services = {
  gvfs = {
    enable = true; # FIXME: does this help wsdd and cli gio stuff???
    package = pkgs.gvfs.override {gnomeSupport = true;}; # unnecessary with the below?
  };
  gnome.glib-networking.enable = true; # FIXME: does this help wsdd and cli gio stuff???
  avahi = {
    enable = true;
    allowInterfaces = [config.networking.interfaces.br0.name];
    publish.enable = true;
  };
};

and I could go on, but pretty much nothing makes a difference. What’s going on?