Blockchain's are only as strong as their networks (distribution/hashing power/relay speed) as that's what gives them power.

A personalized "blockchain" is a hashed database. Without the vast decentralized network, it's pointless.

No, it's very useful! It's called "a git repo, which you can identify by its hash." A completely tamper-evident track record of a history. Without the power consumption of Ireland.

   A completely tamper-evident track record of a history

But they want to be able to alter it.. To regulate bad actors and such.. That won't work for companies if they get hacked and are unable to undo transactions. We've seen this before.

Not yet, but China's National Council for Social Security Fund certainly are in the midst of researching the opportunities to use it.

This is as newsworthy as every organisation ever looking into "Blockchain whatever that is" just in case. You will of course have noticed that it's buzzword of the week. I just got back to work after two weeks' holiday and find myself having to write up something on "Blockchain" for upper mgt., which will mostly be a process of translating profanity-laced screaming into a reasonable-sounding businesslike doubtful tone. "Researching the opportunities" could mean anything, but almost certainly does mean nothing.