It has always been possible to do the conversion to $1 USD worth of STEEM, but the feature was disabled on steemit.com and has not yet been re-enabled. You can still access the feature via other means such as steemconnect.com or steemnow.com
I'm not sure if I'd recommend doing it right now because the price feed is inaccurate and you might not get a good conversion rate. Wait until Binance re-opens for deposits/withdrawals and https://coinmarketcap.com/currencies/steem/#markets is showing less disparity between the exchanges.