The value of the token/coin depends on its usage. Not only the casino platform but the developer should increase the demand for tokens. And along with that should be listed in good exchange. I think currently casino players are increasing but coin prices are not changing accordingly.
In order to increase demand for tokens, it is important to spread the word about that token in the crypto market. A gambling website may have been able to establish a strong foothold in the market, but it doesn't matter that their token price also increases. Gambling websites have no choice but to list on major exchanges to generate demand for tokens. Because when a token is listed on a big exchange, the curiosity about that project is created among crypto investors.