Maybe take others advice and stop commenting on this topic because everything you said is wrong. I’ll contradict all your points using specific personal examples of my usage.
I’ve bought Bitcoin many times without any KYC. In old days localbitcoins and these days ATMs in many countries.
There aren’t any “exchange in the coins path”. I’ve exchanged paper fiat currency at Starbucks, in a hotel lobby.
The wallets I use are open source 100%. In fact I’ve personally written a python script to manually generate a transaction to broadcast. There is no third party. only your operating system, the internet connection and the source code. In that particular case I was using NixOS linux and so my operating system was also open source. I also broadcast my transaction over the ToR network so my internet provider and the Bitcoin network has no visibility.
Now onto usefulness. By holding Bitcoin I’ve preserved and grown my wealth. But how has it been used practically. Lets see.
- yesterday I bought my lunch for my wife and I, $21 using by Bitpay debit card. I loaded the card 2 mins before with those dollars by sending Litecoin which was auto exchanged by Bitpay at exactly the current exchange rate and with no fee. I exchange Bitcoin for small amounts Litecoin periodically as Litecoin is fast and cheap to send for small payments. Savings vs Checking.
- Years ago I met an artist from Argentina on an internet forum. She was painting what I thought were nice paintings. She was selling professional prints of those. I sent her Bitcoin and she sent me the prints. I’ve framed them and they hang in my home. I get many compliments on them.
- I’ve hired a developer in Crimea to work on a security software and he was paid for his work in Bitcoin
- When my sister in law had a baby shower I bought all the gifts at Buy Buy Baby using a digital gift card purchased 30 mins earlier using Bitcoin.
I could actually go on and on and on. But clearly you don’t have experience or understanding of what you are discussing as you proposed sending cash in the mail, which I don’t know anyone who would do that.
Bitcoin is revolutionary and has a decent shot at bringing fiat government currencies to their knees so they are forced to act responsibly and not brr brr money print.