I doubt any exchange tokens, CEX or DEX would be good for long term holding. They carry more risks. For any reason, if any of those exchange fails or something happens (like a major hack or something similar), the tokens would tank them with them.
Not sure why you would want to invest in a exchange token. Other than giving lower fees, what other benefits do they carry? Better stick with bitcoin and regular altcoins.
The same applies to any coin, if there is a hack, it will necessarily have a negative impact on this coin. So there is no special difference between an exchange token and other cryptocurrencies, except that the exchange coin is supported by the exchange itself.
In addition to the reduced commission, the exchange token provides an opportunity to participate in launchpads held by the exchange, in addition there are many different bonuses from its hold.