Update docs to indicate that providers are no longer enabled by defau…

…lt (#1530)

* Update docs to indicate that providers are no longer enabled by default

* Add changes from Blake's review

* touchup

* Update docs/en/ingest-management/elastic-agent/configuration/providers/elastic-agent-providers.asciidoc

Co-authored-by: Blake Rouse <blake.rouse@elastic.co>

* Update docs/en/ingest-management/elastic-agent/configuration/providers/elastic-agent-providers.asciidoc

Co-authored-by: Blake Rouse <blake.rouse@elastic.co>

* Address Blake's comments

* Update docs/en/ingest-management/elastic-agent/configuration/providers/elastic-agent-providers.asciidoc

Co-authored-by: Blake Rouse <blake.rouse@elastic.co>

* Update docs/en/ingest-management/elastic-agent/configuration/providers/elastic-agent-providers.asciidoc

Co-authored-by: Blake Rouse <blake.rouse@elastic.co>

---------

Co-authored-by: Blake Rouse <blake.rouse@elastic.co>

docs/en/ingest-management/elastic-agent/configuration/providers/elastic-agent-providers.asciidoc

@@ -35,8 +35,9 @@ providers:
       - item: key2
 ----
 
-Explicitly disable a provider by setting `enabled: false`. All providers
-are prefixed without name collisions. The name of the provider is in the key in the configuration.
+Providers are enabled automatically if a provider is referenced in an {agent} policy.
+All providers are prefixed without name collisions.
+The name of the provider is in the key in the configuration.
 
 [source,yaml]
 ----
@@ -92,9 +93,11 @@ configuration.
 [[disable-providers-by-default]]
 === Disabling Providers By Default
 
-All registered providers are enabled by default.
+All registered providers are disabled by default until they are referenced in a policy.
 
-Disable all providers by default and only enable explicitly configured providers by setting `agent.providers.initial_default: false`.
+You can disable all providers even if they are referenced in a policy by setting `agent.providers.initial_default: false`.
+
+The following configuration disables all providers from running except for the docker provider, if it becomes referenced in the policy:
 
 [source,yaml]
 ----