That being said, the idea of building a dedicated layer just for casinos is a bit overkill IMO. I dunno if anyone needs a new blockchain for their gambling activity, not to mention the security of that new chain is questionable if nobody supports it. Using a stronger network would be preferable, since the users can interact with web3 easily since years ago already, CMIIW.
Building up a new blockchain or a new layer on top of an available blockchain is risky. If we already have good blockchains to use, no company will want spend resources from human to financial for building up their own ones with risk of compromise, hacks, money steal and more. They can simply deploy their tokens on available big blockchains like Ethereum, Binance Smart Chain, Solana and have less risk of security as well as save a lot of cost for development, test, security, maintenance too.
I agree, any blockchain is already enough for our transactions; besides, casino games are not decentralized—they have their own providers.
The importance users ask for is provably fairness of games they want to play. Because with Provably Fairness, users know that they are treated fairly and it is verifiable too. So casinos won't be able to build up shady games and turn negative results, failures to users for their business profit while users have no ways to know about this unfairness and can not prove it.