My first intention was to mainly base my ranking on their balance sheet, but the balance sheet of SVB, Signature, Silvergate and Credit Suisse was average, it wasn't terrible (Many banks do much worse). In fact Moody's gave SVB an A rating.
What broke SVB,Signature and Silvergate's neck was their lack of diversification, their high exposure to crypto and tech startups and the bankrun that ensued when crypto collapsed and VC cut their funding.
Almost every bank can't sustain a bankrun. In the "cash equivalents % of total assets" column you can see how much of their assets the bank can actually let people quickly withdraw and it isn't that much.
Silvergate had 40% of their assets in cash equivalents, more than almost every bank, and they still failed.
• credit unions have larger reserves. Often 10+%
• credit unions are less likely to be holding massive bundles of securities for which they'd have to write down losses during a sale.
• credit unions tend to have less exposure to uninsured depositors (i.e businesses or people who are just flush with money)
• credit unions are not-for-profits under 501. It's either 501(c)1 or 501(c)3 depending on the credit union from what I recall, but the consequence is that they're federally tax free. Which of course means more money to support the membership.
• there's not really a share price for a credit union other than maybe whatever it cost to open the account. So there's no way to gauge public sentiment around exposure anyway.
Hope that explains why.
Still, if the source data includes these institutions and it makes sense to add them, I would be very interested in seeing how for instance Britain's Nationwide or Spain's Caja Rural compare with publicly traded banks in this ranking of numbers that to be honest I don't really understand well enough to evaluate them.