Probably doesn’t help that this is very a niche bank. Lots of orgs running their payroll from this bank, but few retail account holders.
At a typical community/regional bank, payday is just a bunch of bill entries: debit the corp account and credit the employees accounts. Meanwhile a business-focussed bank will just have huge debits every Friday without corresponding credits: those are happening at other banks.
And with a small number of account holders, it doesn’t take many actors to cause an a bank run.
Payday sealed the fate here.