A blockchain or distributed ledger is an archive. Every node participating in the blockchain synchronises with the other nodes and can retrieve a full copy of the historic blockchain - i.e. the entire archive. Because we cannot delete a record or transaction with the distributed ledger, it does not provide a way to purge them, even if the objects concerned expired over 6 years ago. We can neither remove individual transactions nor previous blocks because the integrity of the distributed ledger depends on all historic blocks being present and the previous block hashes matching, in order to link the blocks together. If we remove blocks or transactions from the ledger, then we destroy its integrity. You have correctly identified one of the 'features' of distributed ledgers, namely that they grow continuously over time - and with no possibility of archival or purging of archaic transactions or blocks - because the integrity of the current blocks depends on the ex istence and availability of the historic transactions and blocks - otherwise transaction history could have been fraudulently rewritten.