Last time I checked Binance they still charged a fee for all trades and reduced it if you owned BNB.
Below is the announcement they have made about zero trading fee for 13 bitcoin pairs. It does't say anything about holding BNB and that doesn't seem to be required.
Binance Launches Zero-Fee Bitcoin TradingOf course, I am not using binance and will never use it. So, I can't confirm this.