The purpose behind Bitcoin was/is to create a type of money that removes the need to trust a middleman (bank), or trust an issuer (central bank). i.e. it’s peer-to-peer, just like cash, with a fixed inflation rate, and its control is distributed to thousands of computers around the world.
Governments can create more money from thin air whenever they want. When they do, they dilute our cash. When we see house prices “go up”, it would be more accurate to say that our pounds have “gone down”.
The fixed supply of Bitcoin, like gold, means its value cannot be diluted. And the privacy aspect is just a logical part of it, given that it’s intended as a replacement for cash, and what I do with cash is also anonymous (yet issued by governments).
And yes – all cryptocurrency wallets are effectively payment terminals. You just generate a QR code with your address + amount you want, the other person scans the QR code with their crypto wallet and the money is sent. Like Paypal, except not controlled by a corporation who could censor you and charge you whatever they want.
Someone recently transferred $1 billion for a $0.68 fee – https://cointelegraph.com/news/bitfinex-made-a-11-billion-btc-transaction-for-only-068
Despite what you read in mainstream media, this tech will be as world-changing as the internet has been. I expect it to be far more dramatic, actually.