He can withdraw his money, but he can't trade or exchange in any solution. So he must withdraw x, y and Z coins, he can't exchange them all to BTC so then withdraw Bitcoin.
He can't trade or exchange coins from an unverified account. All he can do is to withdraw his coin.
However, there is still a way to trade on binance without passing kyc, actually, without even having an account. You can do this by using the Safepal wallet. Here is a thread explaining how it works where many members tried it and confirmed that it works:
Trading on Binance Without KYC via Safepal