This is already required for new books published in the US, and has been for more than one hundred years.
replyIt’s called “mandatory deposit”
Actually - most jurisdictions that issue a publisher a unique root ISBN number have a stipulation that anything new published using that number must have a copy sent to them.
replyLooked into this a decade ago for publishing eBooks via my personal corp when eReaders and ePub were starting to hit big in the mainstream.