You know, mate, since I started using Bitcoin, I have used it to make so many payments across five or more countries now, of which, if it were through a centralized system, the fee would be high and there would be no privacy because those authorities that would process the transaction would know who the money was coming from and where it was going, but with Bitcoin, no one would even know that I had carried out any transactions apart from me and the receiver. Although the transaction can be recorded on the blockchain, no one would know it was me who carried out the transaction. So, Bitcoin has really been a good technology in terms of investment and decentralized payment. Yes, every Bitcoiner is aware of the millionaires and billionaires that have emerged through Bitcoin investment, it may not have been easy for some people to make the money they have without Bitcoin in the picture. Bitcoin will still make some people Wealth.
I agree with you, Bitcoin and other cryptocurrencies have served as a good alternative to fiat for trances border transactions unlike before when it take days to weeks to send money from one country to another, with all it risks of losing privacy and high fees but now with Bitcoin one can send ten of thousand of dollars to love one without delay and haven't to break the bank for that, with just few dollars fees, and if you think that bitcoin network is too congested or feel is high you can chose from other stable cryptocurrencies with cheaper fees and faster transaction time which are all better alternative to Bitcoin.
But in most cases, bitcoin is being used for trances border transactions due to its popularity and stability among others.