doc(autoinstall): Remove incorrect statements, be more direct

doc/rtd/reference/faq.rst

@@ -15,21 +15,15 @@ Having trouble? We would like to help!
 - Find a bug? Check out the :ref:`reporting_bugs` topic to find out how to
   report one
 
-``autoinstall``, ``preruncmd``, ``postruncmd``
-==============================================
-
-Since ``cloud-init`` ignores top level user data ``cloud-config`` keys, other
-projects such as `Juju`_ and `Subiquity autoinstaller`_ use a YAML-formatted
-config that combines ``cloud-init``'s user data cloud-config YAML format with
-their custom YAML keys. Since ``cloud-init`` ignores unused top level keys,
-these combined YAML configurations may be valid ``cloud-config`` files,
-however keys such as ``autoinstall``, ``preruncmd``, and ``postruncmd`` are
-not used by ``cloud-init`` to configure anything.
-
-Please direct bugs and questions about other projects that use ``cloud-init``
-to their respective support channels. For Subiquity autoinstaller that is via
-IRC (``#ubuntu-server`` on Libera) or Discourse. For Juju support see their
-`discourse page`_.
+``autoinstall``
+===============
+
+Other projects, such as `Subiquity autoinstaller`_, use cloud-init to implement
+a subset of their features and have a YAML configuration format which combines
+``cloud-init``'s cloud-config with additional autoinstall-specific keys.
+
+If you are an autoinstall user, please direct questions to their IRC channel
+(``#ubuntu-server`` on Libera) or Discourse.
 
 Can I use cloud-init as a library?
 ==================================