Gamblers will bet on the currency of their choice. However, those who participate in gambling are essentially placing bets by accepting the risk. Professional gamblers don't care if Bitcoin is 100k or not. It doesn't matter to them if they lose the bet by Bitcoin Hughes because they are essentially betting on risk. But in a pumping market it is definitely wiser to hold or bet with stable coins than to bet with bitcoins.
That is true, gamblers will always play no matter what the price of btc is in the market.