If you don't want to use Templates for Blog Posts in all spaces, you can disable the app following these steps.
To disable specific blog templates, use this documentation: Disable specific blog templates
In the space configuration, you can disable the Templates for Blog Posts for Confluence for the specific space by selecting “Disable”.
If a template is disabled globally (see below), you can't enable it for a specific space.
In the administrator configuration, you will see the list of all spaces and can enable or disable the app for specific spaces. The app is enabled for all spaces as default.