Second addendum: If forwarded emails / memes / social media posts are in fact incurring meaningful storage costs, then:
- Note that text storage costs are minuscule next to media attachments
- Note that media attachments are frequently forwarded unmodified
- We have perfectly good patterns for refcounted shared object storage that would make media forwarding costs close to zero
- And I imagine larger cloud email services may already use them
- So…yeah