How can I bulk delete old assets, images, files, etc.?

We have a corporate retention policy which requires us to delete communications older than three years. Unsure why it's so hard to mass delete assets, images files, etc. I expected to be able to select multiple campaigns or images, etc. and have the option to delete. But now we have to manually delete 6000+ assets individually. This seems like a HUGE flaw or lack of basic functionality and should be available without requiring APIs or hiring a vendor to delete old content. Does anyone have any insight or examples of how you handled a similar situation?