Then it will be a terrible currency system. Number of the users will be limited, and bitcoin can only serve a small group of people. Other program will replace bitcoin one day.
That's certainly true, mate. If Bitcoin doesn't scale to the wider public, then it cannot be used as a currency. It would only be useful as a store of value, just like Gold. As you've said earlier, another cryptocurrency might replace Bitcoin sometime in the future, if it proves to be secure, faster, and cheaper than Bitcoin. The technology is already there to make Bitcoin scale to millions of TPS at the lowest cost possible. However, it would be up to the people to adopt new scaling solutions to help make Bitcoin a better cryptocurrency.
Otherwise, existing centralized payment solutions would stay on the lead for quite some time. Bitcoin and Blockchain technology need to beat out centralized systems like PayPal and Visa, to effectively remove the middleman once and for all. Only then, Blockchain would've achieved its true purpose by giving the people sovereignty over their own money.
Nonetheless, this will be long story that might never end if no scaling solution is put up to the test. Just my thoughts
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