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One thing that probably distinguishes plugins from core work is the impact on schemas. When it comes to new functionality added to the metadata resolver, attribute resolver, or filter services, which are essentially the remaining components that rely on "custom" configuration schemas, it will be much simpler to continue to include those components in the core software in order to prevent further pollution of the configuration by other XML namespaces to prevent conflicts. An example of this is a new feature to support decrypting data in the attribute resolver. The TOTP feature requires the ability to potentially decrypt token seeds, so rather than build that into the feature directly, a more generic capability was added to the core, and the plugin can leverage that feature for its specific needs.