I really agree if BNB Coin got Binance is one of the good altcoins for long term investments, because the binance exchanger has a system where there will be new projects that want listings on Binance Exchange, will be given a discount if They pay with BNB coin. It really means that when more altcoins want to register on Binance Exchange, there will be a lot of requests to buy BNB coins. With so coin bnb prices can go up high ahead.
Binance leads among the exchanges in the market, some exchanges are also issuing an exchange token or coin for their investors, they follow the model of Binance because they see how successful it is.
The price of BNB now maybe high already but it's not overvalued with the achievement of the project as of now.
They don't only focus on their centralized exchanges, they have their own chain right now and they are developing the decentralized exchange of their own which they believe the future of exchanges. Also, we've seen how Binance did not let the US traders get out of their exchange, they comply with the US law to still cater them.