Main Ideas Behind a Block Chain Like Ethereum

Below are a few questions/issues I wanted to discuss. In some cases I am playing devil’s advocate somewhat and don’t necessarily support the views expressed:

The main ideas I see behind any blockchain based currency like Ethereum are Decentralization and the idea of a Currency that has a favorable inflation rate compared to most fiat currencies.

First, the idea of decentralization. How valuable is this really? Cyber attacks against US hospitals and other institutions by foreign groups have been on the news frequently. Had these institutions used block chain to store their data, would it have been more safe?

Aside from the issue of outside threats, and solely dealing with the issue of internal threats within a company, isn’t the market itself a sufficient mechanism to keep centralized institutions reasonably under control? If a business is untrustworthy with people’s data, they will soon be out of business, so are incentivized to be honest (there are of course many cases where the institutions failed- e.g. Enron and predatory lending firms in 2004). These failures, however, were the result of human decisions about the company that blockchain, which specializes in keeping track of data, could not have prevented I don’t think.

The second idea of Blockchain as a way to create currencies more stable than fiat: If we agree that centralization is not inherently bad and can work for the most part, there is no reason why a private company can’t issue it’s own currency with inflation rules that the company creates and which are voted on by the board or stock holders. Banks issued their own currency regularly in the 19th century and it seems things worked well at least for a while and I see no reason why this couldn’t work today.

So, the strongest case I see so far for a blockchain is to keep data secure from third party attacks (and I’m not even sure this is a good use case for blockchain and will rely on someone more knowledgeable in this area for that question).

The las question, which is technical, is say we have a blockchain in use to keep a company’s data secure. A chain like ethereum requires you to pay with eth to use the blockchain. Is the reason for this a way to create a demand for eth, or are there other fundamental reasons? For example, could you have a blockchain where people pay dollars to use it?

Edit- I’ve owned eth for 2-3 years now and find the concept interesting. I’m just trying to do a sanity check here and add a healthy dose of skepticism so I don’t think I’m investing in a tulip craze. Blockchain is still kind of elusive because we don’t often see people in our life using it, although it’s written about all the time.

Thanks