mastodon also downloads remote media from all known accounts with no real way to manage it, making it a nightmare to administer disk usage for any decent sized instance. they go the route of your instance being responsible for all remote media, not the other way around
Each server could have an address that you type into a browser. We could have a 'domain name server' that keeps a list of which address should match to which server.
Then people could easily navigate to cat pictures.
p2p cats for teh win