the smart thing to do would be to save a 100 x 100 pixel "avatar" version of an image to act as a checksum plus the addresses of five highest resolution matches of that image found online.  then display the highest res version that loads first and matches the avatar visually.  almost every image posted on Nostr was originally downloaded from somewhere online where it is already hosted for free.  those images which are original can be marked as such by user, but frankly the user should just host those himself.

there is no need to save 10 different copies of an image every time somebody posts a picture of Putin riding a bear.