I don’t know if this is something that is being considered, I’m not the dev. But this is something that is already possible.
You can create an acf/load_field filter on for the flex field. In this filter you can remove the field groups not being used on the site.
You could have a configuration setting of some type where you specify what layouts should be included. There is also the possibility of an options page where you can set the layout to use and then use this in your filter to remove the ones not being used.
