More and more people are waking up to the stupidity of the fiat system on the daily.
El Salvador adopting bitcoin is just the first step in many to come when it comes to the institutional and nation-wide adoption of cyrptocurrencies. Once the mass adoption process is complete, it is inevitable that Defi will be required to build on top of these existing crypto infrastructures and to leverage technology to increase transactional efficiency.
That's very optimistic of you. But I don't think "De-Fi" will actually beat banks since Fiat is too hard to beat. It will co-exist with "Ce-Fi" for many generations. What's important is that people have an alternative to the current monetary system subject to manipulation, fraud, and corruption. As long as people have an "escape route", there should be nothing to worry about. "De-Fi" has always been about bringing "banking to the unbanked", and so far, it's been doing a pretty good job at it.
Of course, "De-Fi" is not perfect. The concept is still fairly new in the mainstream world, so expect some bumps on the road ahead. Volatility and certain vulnerabilities, can make "De-Fi" a lot more riskier than "Ce-Fi". Not many people are able to deal with these risks, so they turn to banks instead. Some countries are embracing "De-Fi", so it should only be a matter of time before it becomes a "force to reckon" with. Just my thoughts