Checkout the GNU name system https://www.gnunet.org/en/gns.html

However, the problem is inherently "{unique, short, decentralized}, pick two". GNUnet allows everyone to freely build their associations of names to public keys. But people still desire globally unique urls they can share and print on paper, so naturally, distributions will still package such "root certificates" by default and most people will trust the same provider of "com". But it's easy for anyone to share their own set of name-key pairs and for users to decide to call them "com" instead, for example if the original organisation managing .com censors some domains (stops published a record signed with their key). However, one would then need to translate urls when sharing them to others, or convicntthem to reconfigure their systems