One thing to bear in mind is that "failing" is not binary. The story seems to be that SV put all their deposits into 10 y bonds in 2021. I'll use that as an approximation. A 10Y bond will usually move about 8x as much as the underlying interest rate (it's called "duration"). So if SVB did nothing but buy these bonds and sit on them, then they would have lost about 36% on these (8 x 4.5% rate movement). That's a lot b…
A bank that can't pay back 100% of deposits has failed. This isn't equity where haircuts can be expected at times; depositors absolutely expect to be able to get back all of their money when requested.
Well, not at the same time. No bank can do that.