I'm going to drop my honest opinion about this because everyone has their opinion because this is a highly objective discussion. When casino started, they were physical platform and they weren't many, eventually internet became a thing where people go and play but crypto like Doge and Bitcoin became the big thing that cause developers eye, people started creating crypto casinos and that was the beginning of new thing in crypto, there wasn't really KYC back then.

Suddenly, when when anti-money laundry became a law when centralized exchanges began to go from no KYC to a KYC exchanges, other casinos to comply but there wasn't attention that much until every casino wanted to be having crypto and because of money laundering concern, they have to go fully KYC. If as a casino company, you open one and you weren't licensed yet for some reasons, you can do your thing but you have to be ready for any case against your casino for any crime. That was what happen to Binance and US settlement of $4B sue. Now as a customer, it's your choice to KYC or don't gamble on casino that request for KYC.