My guess is that Binance experienced a technical issue that prompted them to disabled Steem withdrawals.
I don't have personal experience with Binance here but I read in a post by @kirkins that Binance disabled deposits and withdrawals after the blockchain stall at block 23,847,548. From my understanding, there was a bug in the Steem protocol implementation that allowed an invalid transaction to be included. A week later, the invalid transaction triggered a network halt as it resulted in an invalid operation.
16 days does seem excessive for Binance to respond to this issue, which was patched shortly after it occurred. I am not sure whether Binance runs the type of node which would need to update its version to move past the halt... anyone know?
Thanks for stopping by and answering my call. Now I know the root cause, but what remains a mystery is why it is taking so long to get the node back up and running.
The response from another member below, socky, goes into even more detail.
FYI - Binance has lifted the STEEM withdrawal suspension.