So apparently there's like 4-6 million bitcoin that are lost and gone? Just curious if there was any ideas or plans to update the protocol to replace the lost bitcoins if there was a consensus, if that is even possible.
So that thieves (who did not the actual owner of the coins) will be claiming lost coins?
They should prove with their private keys that they are the owners.
You can not know the exact number of bitcoin that are lost because you can not say all coins that are not moved to another address are lost.