The problem with blockchain is that everything you can do with it can also be done with a good database. In the case of crypto, it also means that you have to download THE ENTIRE THING SINCE IT STARTED if you want to run a full node capable of validating transactions. The Bitcoin Blockchain was - as of September 2025 - 674GB in size, adding a gigabyte every few days, meaning it is probably around 750GB today, stored on every single full node - what a waste of space. Databases are a lot more flexible in that regard.