I trust banks because its the traditional way to keep money and its been around for many centuries the only downside is their adoption level in crypto currency is very low, but we cannot blame them for doing that It takes a lot of debate before they accept the nature of crypto.
The most important thing is that all the money we keep in the banks is guaranteed full by the state, it makes us never hesitate to save in banks, and for tens of years I saving until now have never found a big problem and all money is safe.