In essence, instead of (or maybe in addition to) having a hard-coded list of file types that Archivematica will always remove (like .DS_Store) there would also be a way of configuring what file types to remove, or deaccession, during processing.
We haven't determined yet if this particular task is a high priority for inclusion in the project, and if it is, what implementation will look like. For example, maybe it makes sense to choose file types to deaccession on the fly while processing, or maybe it makes sense to configure this option in the administration tab.