Digital assets that are listed in Binance gains high liquidity so this is not a huge suprise. It has always the most volume and I'm sure that there are a lot of whales hanging out there and just cutting their orders just to make it look it's a normal buy and sell orders. If I were to decide I would want only 10-20 exchanges that will exist in the market so Binance will have 80% or more of the total volume of the whole crypto market.
Not too many exchanges haven't revealed their actual value but Binance is one of the exchange with highest actual trading volume on it so it is not a surprise that people trading on it getting some profits.And they also have BNB to cur down their fee which gives some encouragement for the people who want to trade regularly with crypto on that exchange.