Yes, really very bad news for the KEY because now slowly they are developing the thing and this makes the reputation for this coin may decrease. They are delisting because it is not able to generate enough volume in Btc Pairs. Maybe USDT pair will remain active on Binance exchange.
Well, I'm not sure what's the criteria of de-listing. I admit that KEY/BTC pair wasn't doing very nice, but it was still doing better than at least 8-10 listed BTC pairs which are still present at Binance. Usually, once Binance de-lists the BTC pair, they don't hesitate in removing the remaining pairs as well. So IMO, unfortunately, things are not looking very nice for KEY trading.