The deprecation process should include a way to keep users from creating new stacks with a resource.
When a resource is marked HIDDEN as the final step in the deprecation process, users can still create stacks with that resource. This could result in an ever-growing number of stacks with the unsupported resource. Since removing a resource entirely will break live stacks that contain that resource, it would be difficult to ever remove the resource. Even if the resource is unsupported, some level of maintenance would be necessary to ensure the resource continues to load.
Modify the HIDDEN SupportStatus to disallow creation of stacks that contain HIDDEN resources. This will result in fewer stacks with the unsupported resource over time, making complete removal of the resource a future possibility.
Leave HIDDEN as-is and create a new DISABLED status with the proposed behavior.
Some investigation is needed, but it may be possible to pass a parameter that indicates a create is being done as a result of an UpdateReplace exception. When the flag is encountered for HIDDEN resources, the create will be allowed. It will be disallowed for new resource creates, during stack-create and stack-update (ie. adding a new resource to an existing stack).