I have also seen the above thread/issue before and i also think huobi should update their verification page regarding requirement of verification to withdraw bitcoin too.
But if they don't allow verification document of American citizens why they haven't stopped accepting american traders to register in their platform creates bigger question regarding their business policy.
Thats what I am saying. Im sure I could deposit unlimited BTC to my address but I cannot pull it. Its the fact the verification page says "no verification needed to deposit/withdraw" then they force you to verify to withdraw that makes it shady. It almost seems like they want people information for more than just withdrawals. I use a separate bank account for crypto and personal banking. Many users especially newer users use their regular personal accounts for crypto. I only place money in my crypto-dedicated bank account when I am buying/selling from coinbase. Makes me weary for their non-USA customers. As crappy as America is most of the time they do have high safeguards and monitoring of the banking system. I wonder how many of their customers personal info has hit the black market.