that's right, if BNB falls it will affect binance. that's why we see binance team always maintain BNB coin so that it always has good movement and can survive.
the number of networks provides many choices for us, users. and this is very good because we see good competition.
Not sure about that. If Binance fail, then no doubt Bnb is going to fail but if bnb fail, Binance can somehow manage to continue and they will continue to make their revenues as usual because people love and support Binance, it's now beyond the regular exchange we used to see back then, it's now back and supported by billionaires around the world.
For Binance to be number exchange globally, you should know for sure there are billions investments on the exchange but they will not reveal them to us the public because if Binance fail today, I'm very sure that half of the market will be down.