There's also the case that binance said any usdt or usdc deposited there would be converted to busd, I think that also makes it much riskier than usdc and usdt because of that (you're relying on multiple assets).
The excluded tether because of its huge volume so far in the platform but if you deposit USDC, TUSD or USDP, they would automatically be converted to BUSD
They also delisted any trading pairs of USDC, TUSD or USDP