If it's not intended to be a decentralized system in the first place, the "blockchain" aspect is useless and turns from being a clever hack that allows to generate a certain level of trust from distributed participants, thus enabling the decentralization in the first place, to a marketing ploy that, if not just being lip-service but actually implemented, is a huge resource hog and severely reduces scalability and maintainability of the system without offering any benefits whatsoever.

Because of this situation it is natural to assume that a blockchain-based system must either have a decentralization aspect to it, or that the architects of the system are incompetent. And we don't want to assume there's such gross incompetence at IBM, do we? ;-)

What if the biggest feature about using the blockchain isn't that it's an open ledger that resists tampering from untrustworthy agents but that it has lots of hype?

I guess the "Blockchain" part.

Blockchain is a decentralised way to create trusted record without a trusted counterparty, i.e. centralised.

In this case, there is nothing decentralised, you need to go through IBM as with a regular system. Blockchain is only mentioned as marketing to convince you they are reliable. A bit how some hosting service tell you their are using S3 to convince you they are not going to lose your data.

edit: The problem is the title of the article that let you imagine there is some interesting blockchain tech being developed. Instead that's about as interesting as "Walmart uses SAP"

Being "peer-to-peer distributed" (aka "decentralized") is a fundamental part of the definition of what a blockchain is.

This article explains it well: https://berk.es/2018/09/19/the-private-blockchain-fallacy