the bottleneck here is that most governments have no defined taxation laws yet when it comes to crypto gambling sites. fiat system may be outdated but this traditional payment system will not go away anytime soon. a lot of gamblers are still using it. remember, crypto users are still in small percentage as compared to global population. so it would really take long time before we see the majority of gamblers that will go into crypto
The majority still use fiat for online gambling and physical casinos but online crypto casino campaign in various sports competitions allow crypto casinos to grow even more in the next few years. People need time to switch to using a new currency in gambling while they also need to know what crypto is before they actually know how to use it.
Although currently the growth of crypto gamblers in online casinos is good but basically not big enough compared to the use of fiat in gambling. This is a time of transition from fiat to crypto, gamblers and governments may be preparing to accept and regulate taxes.