There aren’t that many situations where that it actually useful. A blockchain where everyone is equal also means that any mistake requires far more effort to c

There aren’t that many situations where that it actually useful. A blockchain where everyone is equal also means that any mistake requires far more effort to correct and nearly any system we have still needs some sort of centralized governance. In your example publishing news well corrections and retractions can and do happen all the time and sure you’ll say well then just assume that the updates have to have the same key but that still doesn’t solve the problem you are worried about since the bad actor in this case would either have direct control or influence over the news organization so they can still force them to push a “malicious” update. Then we get to the issue that a blockchain isn’t suitable for storing large pieces of information so in this case what would be published to the blockchain is just a link you can still either edit or remove the content that is referenced by the blockchain since the content itself isn’t on it. A blockchain is a classical example of a solution in search of a problem. In fact it might be the most technically correct example of that term I ever encountered. Other examples I often hear about such as health records and land or vehicle registrars etc also don’t benefit from being on the blockchain as those are all heavily regulated and complex processes which are prone to mistakes and using a blockchain won’t solve those issues. The only remotely plausible situation where a blockchain could work is voting however like with all electronic voting the moment you need a PhD or multiple ones to be able to understand how the system works and even then you won’t trust it completely the overall trust in the result would be completely eroded which defeats the whole purpose of having a more reliable system on paper in the first place.