What is BUSD and why does it affect withdrawals of an unrelated token?
BUSD is another stable coin pegged to USD, like USDT and USDC. What they're saying is that you can't withdraw USDC, but you can withdraw any of the other two.
It feels a bit like saying "Unfortunately, converting Facebook Dollars to Apple Dollars is currently not possible due to minor technical difficulties. However, you can still easily convert to Oculus Dollars or Instagram Dollars..."