nixos/activation/bootspec: drop problematic comment, only generate bootspec when bootspec is enabled

nixos/modules/system/activation/bootspec.nix

@@ -50,7 +50,7 @@ let
             --arg init "$out/init" \
             < ${json} \
             | ${pkgs.jq}/bin/jq \
-              --sort-keys \ # Slurp all specialisations and inject them as values in .specialisations.{name} = {specialisation bootspec}.
+              --sort-keys \
               '.v1.specialisation = ($ARGS.named | map_values(. | first | .v1))' \
               ${lib.concatStringsSep " " specialisationLoader} \
             > $out/bootspec/${filename}

nixos/modules/system/activation/top-level.nix

@@ -79,7 +79,7 @@ let
 
       echo -n "${toString config.system.extraDependencies}" > $out/extra-dependencies
 
-      ${optionalString (!config.boot.isContainer) ''
+      ${optionalString (!config.boot.isContainer && config.boot.bootspec.enable) ''
         ${config.boot.bootspec.writer}
         ${config.boot.bootspec.validator} "$out/bootspec/${config.boot.bootspec.filename}"
       ''}