Fiat is a pyramid scheme with an endless supply. Central banks are a relic of an old age money business.
It is pretty much obvious that both are going to become redundant in the future, when you have a money (Bitcoin) - which not only fulfills all the necessary requirements to be a currency but also adds new factors.
Think of VCR's and DVD's. The VCR became redundant after the DVD was introduced, which became useless as new and better technology was introduced. And what happened to those businesses that relied heavily on the old system? They went out of business due to a lack of adaptation. One example of such a business would be Blockbuster.
You gave a not entirely successful example. VCRs and DVDs are products that tend to periodically become obsolete due to the fact that new technologies are constantly developing and improving. But central banks are not a commodity. Central banks are part of the state, part of the system of government and government. So far, humanity has not come up with any new state institutions that could replace the banking system in the state. Banks, of course, will not last forever, but so far there is no replacement for them and it is unlikely to be expected.