Typically AEM allows to have ACL (Access control) based on folder structure and then it by default applies to hierarchy under that node.
We have a use case where we want to have access control based on Template of Experience Fragments with the expectations that any content created using that template will have same access control irrespective which folder the content is created.
That's not possible with AEM ootb. If you have that requirement, your content structure is probably not in-line with the Adobe best practices. Because there access control is a strong factor when you design it.
Can you share some of your requirements which lead you the approach of "create ACL per template"?