It's not killing it, from around the world, there are still so many gamblers who are utilizing Bitcoin and other cryptocurrency for their daily gambling activities, while there are also many other players too that love playing with stable coins. If research is conducted on this, I am assuming that crypto gamblers will be much higher than the numbers of players using stable coins, the reason is because many people that preferred Fiat are using centralized local casinos to gamble but for the many of them using the only crypto casinos, they are betting with crypto.
People who are into crypto makes use of different coins to gamble and this does not have to hinder one over the other from being recognized and continue in adoption, each one of them works perfectly as according to how applicable they have been for their users to engage using them on different purpose, so we are all not going to use one against the other, they all exist to serve their various purpose in gambling and the all were being used for the same purpose.