DeFi or decentralized finance can threaten the world of traditional banking, because of the shift in lending, even DeFi itself is known to be able to provide loans like other traditional banks.
This can affect existing traditional banks, because there will be competition between traditional banks and crypto in general, regardless of the various problems that will occur, crypto and traditional banks must be able to adapt to each other.
Crypto development is progressing so rapidly, this can be seen from the many users who join here, if Traditional Banks close themselves it is not impossible to be abandoned in the next few years.
Although currently crypto is still very risky, it is not impossible that in the future crypto can change finances, just need to wait for regulations or legal regulations, if this happens, it is certain that crypto will grow and be accepted by many people.
I don't have doubts that crypto will continue to progress every year but i don't see it that traditional banks are nearly closing because of crypto. That will never happen as long as the government chose to support traditional banks. However, i always have high hopes that banks will come to adopt and integrate crypto into their bank's transactions. Instead of being one sided, its always better for them both to adapt with each other because that will be the only way that they can continue giving maximum services to the people.