In short term it can lose or gain value.
Exactly. What rises, has to fall one way or the other. We've seen how Bitcoin has increased within a short time frame, to later fall massively in price. It's like a roller coaster where there are ups and downs on the market within specific time frames. This could happen to Binance Coin either in the short or long term. Perhaps, its price increase is given in part to the release of Binance DEX. Not to mention, that there's demand for this exchange-based token because of the many benefits it provides within Binance exchange. Compared to other cryptocurrencies with almost no utility, BNB seems to be the most desirable.
Nonetheless, prices per BNB are still high. Which means, that not many people will be able to afford the token in order to use certain services of Binance Chain. Still, the BNB token might never disappear given that Binance is too big to fail within the crypto industry. Just my thoughts