lazy fetching of the monero blockchain
i assume that 90% of the blockchain are never used
because most transactions i see (event horizon) are only some weeks old
so the full monero blockchain of currently 90GB is mostly a waste of disk space

why no lazy fetching?
let me use a "shallow clone" of the blockchain
and only when a transaction requires deeper access to the blockchain
then fetch to the required depth
and maybe later delete the deep end of the chain to free disk space
