Binance has gained much of its popularity by listing first some tokens that were much sought after, they were listing shady or crappy tokens all the time, it's just that what was considered bad in those times could be said it's gold compared to the crap we have now been added. And yes, the quality dropped like a stone and will continue to drop, Biannce makes money out of trades not out of the value of those coins, they are interested in making people buy and sell not anythign else.