Oh, please, not this again.
Let me copy/paste my reply from
this article:
The whole idea of a blockchain is a ledger that belongs to nobody, and is used, maintained and verified by everybody.
So when someone introduces "their own" blockchain, it means in-house, trust-required, centralized, and owner-dependent, thus essentially stripping it of Bitcoin's innovative advantages.
We already have centralized ledgers and they work quite efficiently - at the cost of putting society at the bank's mercy.
Let's not make the same mistake again.(Author replying that the great innovation of blockchain is about being trustless and imutable, which doesn't require Bitcoin)
But trustless and immutability contradicts with belonging to someone, and being maintained and administered by a single party or authority (such as a bank consortium).
A blockchain operated by a handful of banks is not trustless at all. It fully depends on our trust in them. It's not immutable either: if and when they decide they wish to rollback certain changes or transactions, absolutely nothing stops them from doing so.
It's not necessarily free or open or transparent either (which are other advantages of the Bitcoin blockchain), it would be
their blockchain and
they control what goes in, at what cost, and how much they reveal about it.
Bitcoin solves all this, a custom bank-owned in-house blockchain does not (but of course from their perspective this isn't a problem in the first place).
Actually, from a bank's perspective, having their own blockchain might appear to be a more efficient, cost reducing way of processing their proprietary closed payment data. But for us, the mass audience, the general public or society, exactly what would be the difference?
By the way, I fully agree that trustlessness and immutability are very useful innovations, that don't require Bitcoin. But it would require something else that backs the blockchain, in a decentralized, verifiable, tamper-proof fashion, to provide its trustworthiness, independence and immutability.
Currently there is no such thing. Absolutely nothing compares even remotely to the existing Bitcoin network in terms of the trustless security it delivers, and banks certainly won't provide it.
If you were to set up a secondary network, comparable in size and speed and computing power to Bitcoin's, then sure, you could run a blockchain that is just as secure and trustless and immutable as Bitcoin. I don't see it happening any time soon though.