In the casino's business side, this is bad. But for the people, the consumer, which the main goal of the government to protect, it's perfect.
Also, the chance of revenue that the government will get from casinos' taxes/fees could decrease because of this, less revenue for casinos could affect the revenue that by government gets from them (not sure about this).
It seems you dont understand that this is not going to change anything for the people. Gamblers who wants to spend more of their money gambling can have multiple casinos, splitting the money across those casinos online to gamble. So yea, if you look at it on the other side, the idea is a great one but it wont stop real gamblers, it will only push them to find an alternative way. Apart from taxes, KYC or total restriction, the government can hardly regulate online casinos and gamblers in general.
Yeah this is impossible to achieve online not only they can split fund on different casino but also they can create new account on same casino with the use of different IP since KYC is not mandatory.
They will less likely to be caught if they just play normally since casino doesn’t pay attention much on gambler account that has normal gambling activity.
This law will only applicable on physical casino and all casino that is registered on country gambling regulator.