🍑
It is unfair to see from the gamblers point of view but from the casino's point of view it is very much needed. This can be argued in different manners, but end of the day the gamblers will not stop gambling so they "need" the casinos to run and the casinos "need" the players money to keep itself running while keeping it safe from money laundering.
...
🍑
Casinos need gamblers and gamblers cannot do anything (besides betting) if there are not casinos around. Even though at first we could see this relationship as symbiotic and well balanced, there is a third entity which is involved: regulators and the government. They do not necessarily "need" gamblers or casinos to function or comply with their basic duties, though, the tax from both the casinos and lucky gamblers certainly help to run a country.
KYC and AML were not always a thing, and the relationship worked, but it was also true organized crime had their way with money laundering, they had more liquidity. I see the KYC as a kind of referee within the gambling ecosystem, filtering out "gamblers" with bad intentions and letting alone those who just want to enjoy a service.
Though, it is completely different thing when a shady casino (which may or not lack of liquidity) abuses the referee and turns it against a legitimate gambler who just want to withdraw his money to his personal wallet.