In other words: They are doing something completely different, but still call it "blockchain" because that's the current buzzword.
A blockchain with limited participants is still a blockchain. It's as trustworthy as those participants. If the participants all trust one another, or trust the system to protect them from the others, it serves its purpose, even if they are in fact pathologically lying shitsacks like financial companies.
I'm dubious of the "editing", but if it's really just new records that say "this record replaces record XYZ", i.e., it's still write-only except by convention, that's fine too.
Reminds be a bit of what "cloud" should have stood for until it became a generic moniker for simple online storage.
Not sure what you mean here. Sure lots of marketeers talk about "stored in the cloud", but most often that does mean "stored with AWS or Azure, behind the scenes". And there's plenty of "cloud computing" too: more and more distributed scientific jobs are moving that way, as well as naturally-distributed work like animation rendering. Heck, it's the new fad for small software companies to build and test jobs in the cloud.