The transaction in Bitcoin and other crypto is more efficient and fast for so many players that's why they continue using it but it seems like no body wants to risk so much of their Bitcoin but rather wants to hold it for making profits. That's why there has been other smaller crypto being added by casino so that those that still wants to bet with crypto can use another altcoins and not Bitcoin that they might want to spend.
Back then, holding wasn’t really the main thing. That’s why a lot of people were gambling with Bitcoin because the value was still cheap. It’s only after Bitcoin grew this huge in value, that people started thinking more about holding.
When Bitcoin was still under $500, people loved to gamble with it not just because it was fast, but because there was no KYC. That gave complete freedom. Imagine if everyone back then just decided to hold instead of use it, Bitcoin might not even be at this price today, because adoption wouldn’t have grown this big.
( think of that as well)