Which Blockchain? If you use, for example, .eth on one chain - there's literally nothing stopping me from instigating a new chain which also uses .eth

So you either have to disambiguate names at a protocol level (miki://whatever.eth vs edent://whatever.eth) or at a name level (whatever.eth.miki vs whatever.eth.edent)

Or, you convince everyone in the world to standardise on one chain. In which case, how's that difference from what we have already?