It is really so tough to teach old people about bitcoin, crypto currency and block chain technology. Many people don't know about internet and features of it let alone bitcoin. But if we discuss about bitcoin with them in daily basis, then they may able to understand it.
Yes, we just need to get used to Bitcoin as a daily payment medium that they use. When they interact regularly about this cryptocurrency, more will start learning Bitcoin and also learn about blockchain.
The public only needs a habit to transact using digital currency as the starting point for a decentralized digital currency civilization.