Data storage is in fact not a property of a blockchain. There is nothing that prevents data in a blockchain to be lost other than the fact that many people stor

Data storage is in fact not a property of a blockchain. There is nothing that prevents data in a blockchain to be lost other than the fact that many people store it, which is not guaranteed at all. DLTs (blockchains) solve the double spending problem in a decentral (trustless) way. Thats "the definition" and what separates it from other similar tech like git or synced databases.