I don't know about this and i don't believe this.This is the first time I've heard.I think you made a mistake which is why you are blaming the Bnb.Do you have any such evidence?.You can say details.Everyone makes such mistakes.But you can't specifically blame anyone.Binance and other exchange has no responsibility for what happened to Luna and it's totally different type.
I think traders should be wise about the Luna coin decline, because the Binance exchange only has the right to provide trades but not guarantee profits from the traded coins, so it would be very bad if someone implicates the Binance exchange from the tragedy of the crash on the Luna coin price.