Yes the concept of credit and fractional banking has been a key idea to expand the world economy by allowing banks to lend money they don't actually have, while also making the global economy far riskier through massive debt accumulation and lack of reserves.
With Bitcoin there can be no credit system like that because you can't have fractional banking on Bitcoin. I mean I suppose you COULD start this kind of system but it would quickly collapse as soon as the first economic crisis happened because nobody can just print more bitcoin to make up for what was lent out instead of held in reserve.
The fractional reserve credit economy only works with currencies that are weak and can be printed at will.
Bitcoin should be seen not as a replacement more fiat, but as a new option, an 'escape hatch' as some people call it. Fiat will continue to exist and the world's economic system will continue on as before using fractional banking and printing money and credit, but Bitcoin gives people a way to escape that system when needed. With Bitcoin you can actually save in currency rather than being forced to take on risk through investments. And with Bitcoin you can be sovereign over your savings without needing to hoard a large amount of physical cash which would be very risky.
Bitcoin doesn't replace the national currencies and the banking industry, but it does give every person on the planet the ability to store value in hard money and transact openly with anyone in the world, while also giving people the option to have full sovereignty over their money rather than having to entrust one's money to banks. So Bitcoin doesn't replace anything, but it de-risks people's finances, gives them a financial escape hatch, provides financial sovereignty, and allows people to save/store/grow value with an actual usable currency.
The fiat credit banking system and Bitcoin are two different things and both will continue to exist. Bitcoin is just the world's alternative to the current system, and they each have their own reasons to exist.