There is no other cause of bank failure the but the bank system itself. The banking system is full of flaws that slowly killing the Banking Industry. Like, in order to maintain their operation, they are bound to pay their employee and maintenance. So with greater expenses than profit, It is obvious that the banking system will surely collapse, they are just lucky because they have the support of the government, this at least prolong thier service..
Leads to bank run on Silvergate which shows the Hold-to-Maturity losses
Some customers get worried of their deposits at other banks such as Silicon Valley and do a bank run.
Later Signature, Credit Suisse, First Republic experience more bank runs.
Now it’s WAL and PACW
I do not think it originates from SBF case. First SBF's company is servicing cryptocurrency people, so I do not think there is really any relation between the collapse of some bank to SBF. Second, the bank system is designed to fail unless there is constant refill of deposits .