Now, the question: why it takes THAT long the smaller banks to go the same way and start using the blockchain?
For any company or banks to implement a new technology you need to have a thorough understanding of the system and you cannot implement all the all of a sudden and majority of the technology companies are learning about the opportunities of blockchain for a long time and if the banking sector find it useful for their business then they will implement it.
Of course blockchain will be helpful to banks even growing banks that are not established already. It will help them to secure data and security information that are already stored in their system. Blockchain technology is already being used in certain places and banks shouldn't be an exception.
We can base our point in this article:
https://cryptocrunchapp.com/news/china-launches-blockchain-based-identification-system-for-smart-cities where china based their identification system to blockchain technology. This implies that the future of the banking system in keeping up the records especially the identities of the people will be safe and secured through blockchain technology. Though they didn't apply it to banks yet, we can expect that blockchain technology will not just make each transaction secured, but to keep the people safe as well.