It's the norm in the US (and pretty much everywhere else with well-implemented developed financial infrastructure) for banks to apply extra scrutiny and roadblocks to large withdrawals. There's a patio11 article going over some of the reasons [0], but it notably generates paperwork for the bank reporting the withdrawal to the government and enables a lot of fraud to allow immediate access.
[0] https://www.bitsaboutmoney.com/archive/two-americas-one-bank...